Astrophysics
New submissions
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New submissions for Wed, 1 Jan 20
- [1] arXiv:1912.12300 [pdf, other]
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Title: Probing the interior physics of stars through asteroseismologyAuthors: C. AertsComments: 77 pages, 22 figures (downgraded in resolution to meet the arXiv limits). Invited manuscript submitted to the journal Reviews of Modern Physics, summarizing a decade of space asteroseismology, written for a non-expert broad readership. Comments from the community are welcomed by the authorSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
Years-long high-precision brightness measurements assembled with telescopes operating in space have become available for thousands of stars. Such data made it possible to measure the physics of stellar interiors via nonradial oscillations, opening a new avenue to study the stars in the Universe. Asteroseismology, the interpretation of the characteristics of oscillation modes in terms of the physical properties of the stellar interior, brought entirely new insights in how stars rotate and how they build up their chemistry throughout their evolution. We discuss how data-driven space asteroseismology has allowed us to improve our knowledge of stellar physics. This delivered a drastic increase in the reliability of computer models mimicking the evolution of stars born with a variety of masses and metalicities. Such models are critical ingredients for modern physics as a whole, because they are used throughout various contemporary and multidisciplinary research fields in space science, including the search for life outside the solar system, archeological studies of the Milky Way, and supernova explosions of single and binary stars, among which future gravitational wave sources. We illustrate the specific role and potential of asteroseismology for those modern research fields. We end with current limitations of asteroseismology and highlight how they can be overcome with ongoing and future large infrastructures for survey astronomy combined with new theoretical research in the era of high-performance computing. This review presents some of the results obtained thanks to major community efforts over the past decade. These breakthroughs were achieved in a collaborative and inclusive spirit so characteristic of the asteroseismology community. The aim was to write it in a way so as to make this research field well accessible.
- [2] arXiv:1912.12305 [pdf, other]
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Title: Current Population Statistics Do Not Favor Photoevaporation over Core-Powered Mass Loss as the Dominant Cause of the Exoplanet Radius GapAuthors: R. O. P. Loyd, Evgenya L. Shkolnik, Adam C. Schneider, Tyler Richey-Yowell, Travis S. Barman, Sarah Peacock, Isabella PaganoComments: 27 pages, 32 figures, accepted to ApJSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
We search for evidence of the cause of the exoplanet radius gap, i.e. the dearth of planets with radii near $1.8\ R_\oplus$. If the cause was photoevaporation, the radius gap should trend with proxies for the early-life high-energy emission of planet-hosting stars. If, alternatively, the cause was core-powered mass loss, no such trends should exist. Critically, spurious trends between the radius gap and stellar properties arise from an underlying correlation with instellation. After accounting for this underlying correlation, we find no trends remain between the radius gap and stellar mass or present-day stellar activity as measured by near-UV emission. We dismiss the nondetection of a radius gap trend with near-UV emission because present-day near-UV emission is unlikely to trace early-life high-energy emission, but we provide a catalog of GALEX near-UV and far-UV emission measurements for general use. We interpret the nondetection of a radius gap trend with stellar mass by simulating photoevaporation with mass-dependent evolution of stellar high-energy emission. The simulation produces an undetectable trend between the radius gap and stellar mass under realistic sources of error. We conclude that no evidence, from this analysis or others in the literature, currently exists that clearly favors either photoevaporation or core powered mass loss as the primary cause of the exoplanet radius gap. However, repeating this analysis once the body of well-characterized $< 4\ R_\oplus$ planets has roughly doubled could confirm or rule out photoevaporation.
- [3] arXiv:1912.12314 [pdf, other]
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Title: (Simulating) Coronal Mass Ejections in Active StarsAuthors: Julián D. Alvarado-Gómez (1 and 2), Jeremy J. Drake (2), Cecilia Garraffo (3), Sofia P. Moschou (2), Ofer Cohen (4), Rakesh K. Yadav (3), Federico Fraschetti (2 and 5) ((1) Leibniz Institute for Astrophysics Potsdam, (2) Center for Astrophysics, Harvard & Smithsonian, (3) Harvard University, (4) University of Massachusetts at Lowell (5) University of Arizona)Comments: 7 pages, 2 figures, to appear in the proceedings of the IAU Symposium 354, Solar and Stellar Magnetic Fields: Origins and Manifestations. Eds: A. Kosovichev, K. Strassmeier, M. Jardine; based on an invited talkSubjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)
The stellar magnetic field completely dominates the environment around late-type stars. It is responsible for driving the coronal high-energy radiation (e.g. EUV/X-rays), the development of stellar winds, and the generation transient events such as flares and coronal mass ejections (CMEs). While progress has been made for the first two processes, our understanding of the eruptive behavior in late-type stars is still very limited. One example of this is the fact that despite the frequent and highly energetic flaring observed in active stars, direct evidence for stellar CMEs is almost non-existent. Here we discuss realistic 3D simulations of stellar CMEs, analyzing their resulting properties in contrast with solar eruptions, and use them to provide a common framework to interpret the available stellar observations. Additionally, we present results from the first 3D CME simulations in M-dwarf stars, with emphasis on possible observable signatures imprinted in the stellar corona.
- [4] arXiv:1912.12328 [pdf, ps, other]
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Title: Catastrophic events in protoplanetary disks and their observational manifestationsComments: 13 pages, 2 figuresJournal-ref: Astrophys. J. Lett., Vol. 887, Iss.1, L15, 2019Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Observations of protoplanetary disks with high angular resolution using an ALMA interferometer showed that ring-shaped structures are often visible in their images, indicating strong disturbances in the disks. The mechanisms of their formation are vividly discussed in the literature. This article shows that the formation of such structures can be the result of destructive collisions of large bodies (planetesimals and planetary embryos) accompanied by the formation of a large number of dust particles, and the subsequent evolution of a cloud of dust formed in this way.
- [5] arXiv:1912.12336 [pdf, other]
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Title: Evidence for a multipolar magnetic field in SGR J1745-2900 from X-ray light-curve analysisAuthors: Rafael C. R. de Lima, Jaziel G. Coelho, Jonas P. Pereira, Claudia V. Rodrigues, Jorge A. RuedaComments: 11 pages,5 figures, 5 tables; Accepted for publication in the Astrophysical Journal (ApJ)Subjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)
SGR J1745-2900 was detected from its outburst activity in April 2013 and it was the first soft gamma repeater (SGR) detected near the center of the Galaxy (Sagittarius A$^*$). We use 3.5-year Chandra X-ray light-curve data to constrain some neutron star (NS) geometric parameters. We assume that the flux modulation comes from hot spots on the stellar surface. Our model includes the NS mass, radius, a maximum of three spots of any size, temperature and positions, and general relativistic effects. We find that the light-curve of SGR J1745-2900 could be described by either two or three hot spots. The ambiguity is due to the small amount of data, but our analysis suggests that one should not disregard the possibility of multi-spots (due to a multipolar magnetic field) in highly magnetized stars. For the case of three hot spots, we find that they should be large and have angular semi-apertures ranging from 16-67 degrees. The large size found for the spots points to a magnetic field with a nontrivial poloidal and toroidal structure (in accordance with magnetohydrodynamics investigations and NICER's recent findings for PSR J0030+0451) and is consistent with the small characteristic age of the star. Finally, we also discuss possible constraints on the mass and radius of SGR J1745-2900 and briefly envisage possible scenarios accounting for the 3.5-year evolution of SGR J1745-2900 hot spots.
- [6] arXiv:1912.12344 [pdf, other]
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Title: Colliding Winds in and around the Stellar Group IRS 13E at the Galactic CenterComments: 17 pages, accepted for publication in MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)
IRS~13E is an enigmatic compact group of massive stars located in projection only 3.6 arcseconds away from Sgr A*. This group has been suggested to be bounded by an intermediate-mass black hole (IMBH). We present a multi-wavelength study of the group and its interplay with the environment. Based on Chandra observations, we find the X-ray spectrum of IRS~13E can be well characterized by an optically thin thermal plasma. The emission peaks between two strongly mass-losing Wolf-Rayet stars of the group. These properties can be reasonably well reproduced by simulated colliding winds of these two stars. However, this scenario under-predicts the X-ray intensity in outer regions. The residual emission likely results from the ram-pressure confinement of the IRS~13E group wind by the ambient medium and is apparently associated with a shell-like warm gas structure seen in Pa-alpha and in ALMA observations. These latter observations also show strongly peaked thermal emission with unusually large velocity spread between the two stars. These results indicate that the group is colliding with the bar of the dense cool gas mini-spiral around Sgr A*. The extended X-ray morphology of IRS~13E and its association with the bar further suggest that the group is physically much farther away than the projected distance from Sgr A*. The presence of an IMBH, while favorable to keep the stars bound together, is not necessary to explain the observed stellar and gas properties of IRS~13E.
- [7] arXiv:1912.12347 [pdf, other]
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Title: Exploring the formation pathways of formamide near young O-type starsAuthors: Veronica Allen (1, 2, 3), Floris F. S. van der Tak (2 and 3), Ana López-Sepulcre (4 and 5), Álvaro Sánchez-Monge (6), Victor Rivilla (7), Ricardo Cesaroni (7). ((1) NASA Goddard Space Flight Center, (2) Kapteyn Astronomical Institute, (3) SRON Groningen, (4) CNRS, IPAG, Univ. Grenoble Alpes, (5) IRAM, (6) I. Physikalisches Institut, Universitat zu Koln, and (7) INAF, Osservatorio Astrofisico di Arcetri)Comments: Main text: 15 pages, 17 figures, 10 tables. Appendix: 21 pages, 28 figuresSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)
Context. As a building block for amino acids, formamide (NH$_2$CHO) is an important molecule in astrobiology and astrochemistry, but its formation path in the interstellar medium is not understood well.
Aims. We aim to find empirical evidence to support the chemical relationships of formamide to HNCO and H$_2$CO.
Methods. We examine high angular resolution (~0.2") Atacama Large Millimeter/submillimeter Array (ALMA) maps of six sources in three high-mass star-forming regions and compare the spatial extent, integrated emission peak position, and velocity structure of HNCO and H$_2$CO line emission with that of NH$_2$CHO by using moment maps. Through spectral modeling, we compare the abundances of these three species.
Results. In these sources, the emission peak separation and velocity dispersion of formamide emission is most often similar to HNCO emission, while the velocity structure is generally just as similar to H$_2$CO and HNCO (within errors). From the spectral modeling, we see that the abundances between all three of our focus species are correlated, and the relationship between NH$_2$CHO and HNCO reproduces the previously demonstrated abundance relationship.
Conclusions. In this first interferometric study, which compares two potential parent species to NH$_2$CHO, we find that all moment maps for HNCO are more similar to NH$_2$CHO than H$_2$CO in one of our six sources (G24 A1). For the other five sources, the relationship between NH$_2$CHO, HNCO, and H$_2$CO is unclear as the different moment maps for each source are not consistently more similar to one species as opposed to the other. - [8] arXiv:1912.12358 [pdf, other]
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Title: Time-Dependent, Multi-Wavelength Shock Acceleration Models for Active Flares of 3C 279Comments: 7 pages and 2 figures, accepted for publication in Proceedings of Science for the Proceedings of the High Energy Phenomena in Relativistic Outflows VII - HEPRO VII conference, held in Barcelona, Spain, July 2019Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
Jets in blazars are an excellent forum for studying acceleration at relativistic shocks using the highly-variable emission seen across the electromagnetic spectrum. Our recent work on combining multi-wavelength leptonic emission models with simulated thermal+non-thermal distributions from shock acceleration theory has resulted in new insights into plasma conditions in blazars. This has demonstrated the ability to infer the cyclotron frequency, the plasma density and thus also the Alfven speed, thereby determining the rapidity of particle energization. An important inference was that MHD turbulence levels decline with remoteness from jet shocks. This paper outlines new results from our recent extension of this program to a two-zone, time-evolving construction, modeling together both extended, enhanced emission states from larger radiative regions, and prompt flare events from compact acceleration zones. These are applied to flares in the FSRQ blazar 3C 279 monitored by Fermi-LAT in gamma-rays in late 2013. With impulsive injection episodes from the shock zone, as the acceleration first proceeds and then abates, the radiative simulations obtain a pronounced spectral hardening in the optical and gamma-ray bands as the flare grows, followed by a softening during the decay phase. For 3C 279, while model radio and X-ray synchrotron flares are temporally correlated, there is a lag in both bands relative to GeV gamma rays and optical emission on timescales of a number of hours. This delay is governed by the short cooling time associated with the bright external Compton signal.
- [9] arXiv:1912.12360 [pdf, other]
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Title: Interpreting LSTM Prediction on Solar Flare Eruption with Time-series ClusteringAuthors: Hu Sun (1), Ward Manchester (2), Zhenbang Jiao (1), Xiantong Wang (2), Yang Chen (1 and 3) ((1) Department of Statistics, University of Michigan, Ann Arbor, (2) Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, (3) Michigan Institute for Data Science, University of Michigan, Ann Arbor)Comments: 35 pages, 17 figures, 2 tablesSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Machine Learning (stat.ML)
We conduct a post hoc analysis of solar flare predictions made by a Long Short Term Memory (LSTM) model employing data in the form of Space-weather HMI Active Region Patches (SHARP) parameters. These data are distinguished in that the parameters are calculated from data in proximity to the magnetic polarity inversion line where the flares originate. We train the the LSTM model for binary classification to provide a prediction score for the probability of M/X class flares to occur in next hour. We then develop a dimension-reduction technique to reduce the dimensions of SHARP parameter (LSTM inputs) and demonstrate the different patterns of SHARP parameters corresponding to the transition from low to high prediction score. Our work shows that a subset of SHARP parameters contain the key signals that strong solar flare eruptions are imminent. The dynamics of these parameters have a highly uniform trajectory for many events whose LSTM prediction scores for M/X class flares transition from very low to very high. The results suggest that there exist a few threshold values of a subset of SHARP parameters when surpassed could indicate a high probability of strong flare eruption. Our method has distilled the knowledge of solar flare eruption learnt by deep learning model and provides a more interpretable approximation where more physics related insights could be derived.
- [10] arXiv:1912.12368 [pdf, other]
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Title: Low-temperature chemistry induced by cosmic rays: positive and negative ions desorption from nitrile-bearing astrophysical ice analoguesAuthors: Fabio de A Ribeiro, Guilherme C Almeida, Wania Wolff, Heloisa M Boechat-Roberty, Maria L M Rocco, Enio F da SilveiraSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA); Atomic Physics (physics.atom-ph)
In cold core of dark molecular clouds, where the UV radiation from external sources is strongly attenuated, cosmic rays can induce chemical reactions on the surface of ice-covered grains promoting the ejection of the processed material to the gas phase. We report the positive and negative secondary ion emission from pure CH3CN, C2H3CN and i-C3H7CN ices due to the bombardment of heavy ions (252Cf fission fragments), simulating the incidence of cosmic rays onto icy surfaces. The secondary ions emitted from each sample were analysed by time-of-flight mass spectrometry (TOF-MS), using Plasma Desorption Mass Spectrometry (PDMS) technique. Several ionic species were identified, indicating strong fragmentation on the frozen surface. Proton-transfer processes are suggested to play a role for positive ion desorption, as evidenced by the protonated RCNH+ parent molecules and (RCN)nH+ ionic clusters. The high electron affinity of the cyano radical seems to contribute to the strong emission of CN-, as well as anions attributed to the CHmCN- fragment and (RCN)nCN- cluster series. Sputtering and desorption of ion clusters (positive and negative) induced by heavy ion bombardment are suggested to constitute a route by which new neutral or ionised molecular species may be delivered to the gas phase where thermal desorption is negligible.
- [11] arXiv:1912.12412 [pdf, ps, other]
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Title: Star formation in outer rings of S0 galaxies. II. NGC 4513 -- a multi-spin ringed S0 galaxyComments: 8 paged, 7 figures, accepted for publication in A&ASubjects: Astrophysics of Galaxies (astro-ph.GA)
Though S0 galaxies are usually thought to be `red and dead', they demonstrate often star formation organized in ring structures. We try to clarify the nature of this phenomenon and its difference from star formation in spiral galaxies. The moderate-luminosity nearby S0 galaxy, NGC 4513, is studied here. By applying long-slit spectroscopy along the major axis of NGC 4513, we have measured gas and star kinematics, Lick indices for the main body of the galaxy, and strong emission-line flux ratios in the ring. After inspecting the gas excitation in the ring using the line ratios diagnostic diagrams and have assured that it is ionized by young stars, we have determined the gas oxygen abundance by using popular strong-line calibration methods. We have estimated star formation rate (SFR) in the outer ring by using the archival Galaxy Evolution Explorer (GALEX) ultraviolet images of the galaxy. The ionized gas counterrotates the stars over the whole extension of NGC 4513 so being accreted from outside. The gas metallicity in the ring is slightly subsolar, [O/H]=-0.2 dex, matching the metallicity of the stellar component of the main galactic disc. However the stellar component of the ring is much more massive than can be explained by the current star formation level in the ring. We conclude that probably the ring of NGC 4513 is a result of tidal disruption of a massive gas-rich satellite, or it may be a consequence of a long star-formation event provoked by a gas accretion from a cosmological filament having started some 3 Gyr ago.
- [12] arXiv:1912.12417 [pdf, other]
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Title: Dark Matter Thermonuclear Supernova IgnitionComments: 21 pages, 9 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We investigate local environmental effects from dark matter (DM) on thermonuclear supernovae (SNe Ia) using publicly available archival data of 224 low-redshift events, in an attempt to shed light on the SN Ia progenitor systems. SNe Ia are explosions of carbon-oxygen (CO) white dwarfs (WDs) that have recently been shown to explode at sub-Chandrasekhar masses; the ignition mechanism remains, however, unknown. Recently, it has been shown that both weakly interacting massive particles (WIMPs) and macroscopic DM candidates such as primordial black holes (PBHs) are capable of triggering the ignition. Here, we present a method to estimate the DM density and velocity dispersion in the vicinity of SN Ia events and nearby WDs; we argue that (i) WIMP ignition is highly unlikely, and that (ii) DM in the form of PBHs distributed according to a (quasi-) log-normal mass distribution with peak $\log_{10}(m_0/1$g$)=24.9\pm 0.9$ and width $\sigma= 3.3\pm 1.0$ is consistent with SN Ia data, the nearby population of WDs and roughly consistent with other constraints from the literature.
- [13] arXiv:1912.12473 [pdf, other]
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Title: Hunting dark matter in galaxy clusters with non-thermal electronsAuthors: Geoff BeckComments: 5 pages, 3 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
The electron population inferred to be responsible for the mini-halo within the Ophiuchus galaxy cluster is a steep power-law in energy with a slope of $3.8$. This is substantially different to that predicted by dark matter annihilation models. In this work we present a method of indirect comparison between the observed electron spectrum and that predicted for indirect dark matter emissions. This method utilises differences in the consequences of a given electron distribution on the subsequent spectral features of synchrotron emissions. To fully exploit this difference, by leveraging the fact that the peak and cut-off synchrotron frequencies are substantially different to hard power-law cases for WIMP masses above $\sim 50$ GeV, we find that we need $\mu$Jy sensitivities at frequencies above 10 GHz while being sensitive to arcminute scales. We explore the extent to which this electron spectrum comparison can be validated with the up-coming ngVLA instrument. We show that, with the ngVLA, this method allows us to produce far stronger constraints than existing VLA data, indeed these exceed the Fermi-LAT dwarf searches in a wide variety of annihilation channels and for all studied magnetic field scenarios.
- [14] arXiv:1912.12495 [pdf, ps, other]
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Title: Optical Transmission Spectra of Hot-Jupiters: Effects of ScatteringComments: 20 pages (AASTEX6.2) including 14 eps colour figures. Accepted for publication in The Astrophysical JournalSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
We present new grids of transmission spectra for hot-Jupiters by solving the multiple scattering radiative transfer equations with non-zero scattering albedo instead of using the Beer-Bouguer-Lambert law for the change in the transmitted stellar intensity. The diffused reflection and transmission due to scattering increases the transmitted stellar flux resulting into a decrease in the transmission depth. Thus we demonstrate that scattering plays a double role in determining the optical transmission spectra -- increasing the total optical depth of the medium and adding the diffused radiation due to scattering to the transmitted stellar radiation. The resulting effects yield into an increase in the transmitted flux and hence reduction in the transmission depth. For a cloudless planetary atmosphere, Rayleigh scattering albedo alters the transmission depth up to about 0.6 micron but the change in the transmission depth due to forward scattering by cloud or haze is significant throughout the optical and near-infrared regions. However, at wavelength longer than about 1.2 $\mu$m, the scattering albedo becomes negligible and hence the transmission spectra match with that calculated without solving the radiative transfer equations. We compare our model spectra with existing theoretical models and find significant difference at wavelength shorter than one micron. We also compare our models with observational data for a few hot-Jupiters which may help constructing better retrieval models in future.
- [15] arXiv:1912.12499 [pdf, other]
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Title: Non-linear damping of superimposed primordial oscillations on the matter power spectrum in galaxy surveysComments: 22 pages, 9 figures, 1 tableSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
Galaxy surveys are an important probe for superimposed oscillations on the primordial power spectrum of curvature perturbations, which are predicted in several theoretical models of inflation and its alternatives. In order to exploit the full cosmological information in galaxy surveys it is necessary to study the matter power spectrum to fully non-linear scales. We therefore study the non-linear clustering in models with superimposed linear and logarithmic oscillations to the primordial power spectrum by running high-resolution dark-matter-only N-body simulations. We then derive a fitting formula for the non-linear redshift-dependent damping of primordial superimposed oscillations in the matter power spectrum for $k \lesssim 0.6\ h/$Mpc at $0 \leq z \leq 5$ with an accuracy below the percent. We finally use this fitting formula to forecast the capabilities of future galaxy surveys, such as Euclid and Subaru, to probe primordial oscillation down to non-linear scales alone and in combination with the information contained in CMB anisotropies.
- [16] arXiv:1912.12515 [pdf, ps, other]
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Title: Inflation with very small tensor-to-scalar ratioAuthors: Koichi HiranoComments: 4 pages, 2 figures, 1 tableSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
We have investigated inflation models that predict a very small value of the tensor-to-scalar ratio, $r$. The spectral index $n_s$, and the tensor-to-scalar ratio $r$, are strictly constrained by the Planck data. $n_s$ and $r$ are sensitive to the shape and magnitude of the inflaton potential, respectively.The constraints by the Planck 2018 data combined with other cosmological observations are compared with the predictions from the inflation models regarding $n_s$ and $r$. Furthermore, we discuss the comparison of future tensor-to-scalar ratio data with predictions from the inflation models with a focus on part of the quantum fluctuation origin.
- [17] arXiv:1912.12518 [pdf, other]
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Title: Drifting Pulsation Structure at the Very Beginning of the 2017 September 10 Limb FlareComments: 14 pages, 11 figures, accepted do ApJSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
Drifting pulsation structures (DPSs) are important radio fine structures usually observed at the beginning of eruptive solar flares. It has been suggested that DPSs carry important information on the energy release processes in solar flares. We study DPS observed in an X8.2-class flare on 2017 September 10 in the context of spatial and spectral diagnostics provided by microwave, EUV, and X-ray observations. We describe DPS and its sub-structures that were observed for the first time. We use a new wavelet technique to reveal characteristic periods in DPS and their frequency bands. Comparing the periods of pulsations found in this DPS with those in previous DPSs we found new very short periods in the 0.09-0.15 s range. We present EOVSA images and spectra of microwave sources observed during the DPS. This DPS at its very beginning has pulsations in two frequency bands (1000-1300 MHz and 1600--1800 MHz) which are interconnected by fast drifting bursts. We show that these double-band pulsations started just at the moment when the ejected filament splits apart in a tearing motion at the location where a signature of the flare current sheetlater appeared. Using the standard flare model and previous observations of DPSs, we interpret these double-band pulsations as a radio signature of superthermal electrons trapped in the rising magnetic rope and flare arcade at the moment when the flare magnetic reconnection starts. The results are discussed in a scenario with the plasmoid in the rising magnetic rope.
- [18] arXiv:1912.12538 [pdf, other]
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Title: Full of Orions: a 200-pc mapping of the interstellar medium in the redshift-3 lensed dusty star-forming galaxy SDP.81Comments: 27 pages, 22 figures. 24 MB in total. Submitted to MNRAS (28/9/2019). Data available on requestSubjects: Astrophysics of Galaxies (astro-ph.GA)
We present a sub-kpc resolved study of the interstellar medium properties in SDP.81, a z=3.042 strongly gravitationally lensed dusty star-forming galaxy, based on high-resolution, multi-band ALMA observations of the FIR continuum, CO ladder and the [CII] line. Using a visibility-plane lens modelling code, we achieve a median source-plane resolution of ~200 pc. We use photon-dominated region (PDR) models to infer the physical conditions - far-UV field strength, density, and PDR surface temperature - of the star-forming gas on 200-pc scales, finding a FUV field strength of ~10^3-10^4 G0, gas density of ~10^5 cm^-3 and cloud surface temperatures up to 1500 K, similar to those in the Orion Trapezium region. The [CII] emission is significantly more extended than that FIR continuum: ~50 per cent of [CII] emission arises outside the FIR-bright region. The resolved [CII]/FIR ratio varies by almost 2 dex across the source, down to ~2x10^-4 in the star-forming clumps. The observed [CII]/FIR deficit trend is consistent with thermal saturation of the C+ fine-structure level occupancy at high gas temperatures. We make the source-plane reconstructions of all emission lines and continuum data publicly available.
- [19] arXiv:1912.12539 [pdf]
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Title: Betelgeuse at the end of 2019: an historical minimum about to endAuthors: Costantino SigismondiComments: 4 page, 2 figures, 1 tableSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
The semi-regular variable star Betelgeuse is undergoing an historical minimum of its brightness. An 8 year series of visual and V-band CCD observations started at the end of 2011 is presented and discussed. Visual methods for comparing magnitudes of angularly distant stars, and performing a differential photometry, needed for such a bright star, are also presented.
- [20] arXiv:1912.12554 [pdf, other]
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Title: Spontaneous formation of geysers at only one pole on Enceladus' ice shellSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The ice shell on Enceladus, an icy moon of Saturn, exhibits strong asymmetry between the northern and southern hemispheres, with all geysers compacted over the south pole, even though the external configuration is almost perfectly symmetric. Using an idealized thin ice model, we demostrate that this asymmetry may form spontaneously, without any noticeable a priori asymmetry (such as a giant impact or a monopole structure of geological activity), as opposed to previous studies. Infinitesimal amounts of hemispheric asymmetry in the ice shell thickness due to random perturbations are found to be able to grow indefinitely, ending up significantly thinning the ice shell at one of the poles relative to the other and thereby allowing the fracture formation there. This proposed symmetry breaking is suggested to occur only on small planetary bodies with specific combinations of global mean thickness of the ice shell and surface temperature, consistent with current observations. This parameter regime, once it gets better constrained using more complex models, may be used to predict the ice shell structure on other planetary bodies.
- [21] arXiv:1912.12591 [pdf]
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Title: SKA shakes hands with SummitComments: Published in Science BulletinSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
Recently, a full-scale data processing workflow of the Square Kilometre Array (SKA) Phase 1 was successfully executed on the world's fastest supercomputer Summit, proving that scientists have the expertise, software tools and computing resources to process the SKA data. The SKA-Summit experiment shows the importance of multidisciplinary cooperation between astronomy, computer science and others communities. The SKA science cannot be achieved without the joint efforts of talents from multiple fields.
- [22] arXiv:1912.12597 [pdf, ps, other]
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Title: Fast jet proper motion discovered in a blazar at z = 4.72Comments: Science Bulletin, submittedSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)
High-resolution observations of high-redshift ($z>4$) radio quasars offer a unique insight into jet kinematics at early cosmological epochs, as well as constraints on cosmological model parameters. Due to the general weakness of extremely distant objects and the apparently slow structural changes caused by cosmological time dilation, only a couple of high-redshift quasars have been studied with parsec-scale resolutions, and with limited number of observing epochs. Here we report on very long baseline interferometry (VLBI) observations of a high-redshift blazar J1430+4204 ($z=4.72$) in the 8 GHz frequency band at five different epochs spanning 22 years. The source shows a compact core--jet structure with two jet components being identified within 3 milli-arcsecond (mas) scale. The long time span and multiple-epoch data allow for the kinematic studies of the jet components. That results in a jet proper motion of $\mu {\rm (J1)}$ = 0.017$\pm$0.002~mas\,yr$^{-1}$ and $\mu({\rm J2})$=0.156$\pm$0.015~mas\,yr$^{-1}$, respectively. For the fastest-moving outer jet component J2, the corresponding apparent transverse speed is $19.5 \pm 1.9 \,c$. The inferred bulk jet Lorentz factor $\Gamma = 14.6 \pm 3.8$ and viewing angle $\theta = 2.2^{\circ} \pm 1.6^{\circ}$ indicate highly relativistic beaming. The Lorentz factor and apparent proper motion are the highest measured to date among the $z>4$ jetted radio sources, while the jet kinematics is still consistent with the cosmological interpretation of quasar redshifts.
- [23] arXiv:1912.12600 [pdf, other]
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Title: A gigaparsec-scale local void and the Hubble tensionComments: 11 pages, 8 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
We explore the possibility of using a gigaparsec-scale local void to reconcile the Hubble tension. Such a gigaparsec-scale void can be produced by multi-stream inflation where different parts of the observable universe follow different inflationary trajectories. The impact of such a void for cosmological observations is studied, especially those involving supernovae, Baryon Acoustic Oscillations (BAO) and the kinetic Sunyaev-Zel'dovich (kSZ) effect. As a benchmark model, a 1.7Gpc scale with boundary width 0.7Gpc and density contrast -0.14 may ease the Hubble tension.
- [24] arXiv:1912.12629 [pdf, other]
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Title: Testing the equivalence principle via the shadow of black holesAuthors: Chunlong Li, Sheng-Feng Yan, Lingqin Xue, Xin Ren, Yi-Fu Cai, Damien A. Easson, Ye-Fei Yuan, Hongsheng ZhaoComments: 10 pages, 3 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
We study the equivalence principle, regarded as the cornerstone of General Relativity, by analyzing the deformation observable of black hole shadows. Such deformation can arise from new physics and may be expressed as a phenomenological violation of the equivalence principle. Specifically, we assume that there is an additional background vector field acting on the photons. This vector field changes the way the system depends on initial conditions, and can produce different sizes of the black hole shadow at different wave bands. This can be tested by future multi-band observations. Adopting a specific form of the vector field we obtain constraints on model parameters from Event Horizon Telescope observations and measurements of gas/stellar orbits.
- [25] arXiv:1912.12632 [pdf, other]
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Title: MCMCI: a code to fully characterize an exoplanetary systemComments: 18 pages, 6 figures, 6 tables. Accepted for publication in A&A. Source code will be uploaded on GitHub soonSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
By analysing the transit LC of a planet-hosting star or the induced RV oscillations, many useful information on the planet may be retrieved. However, inferring the physical parameters of the planet (mass, size, semi-major axis, etc.) requires the preliminary knowledge of some parameters of the host star, especially its mass and/or radius, that are generally inferred through theoretical evolutionary models. The paper aims at presenting and testing a whole algorithm devoted to the complete characterization of an exoplanetary system thanks to the global analysis of photometric and/or RV time-series combined to observational stellar parameters derived either from spectroscopy or photometry. We developed an integrated tool called MCMCI that combines the Markov Chain Monte Carlo approach for analysing photometric and/or RV time-series with a proper interpolation within stellar evolutionary isochrones and tracks (known as Isochrone placement) to be performed at each chain step, to retrieve stellar theoretical parameters, such as age, mass and radius. We tested the MCMCI both on the HD 219134 multiplanetary system hosting two transiting rocky super-Earths and on WASP-4, that hosts a bloated hot Jupiter. Even considering different input approaches, a final convergence was reached within the code, we found good agreement with the results already stated in the literature and we obtained more precise output parameters, especially concerning planetary masses. The MCMCI tool offers the opportunity of performing an integrated analysis of an exoplanetary system, without splitting it into the preliminary stellar characterization through theoretical models, but rather favouring a close interaction between the light-curve analysis and the isochrones, so that the parameters recovered at each step of the MCMC enter as input of the Isochrone placement.
- [26] arXiv:1912.12639 [pdf]
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Title: Third components with elliptical orbits in the eclipsing binaries: EQ Tau, IR Cas, IV Cas, RY Aqr & RZ ComAuthors: D.E. TvardovskyiComments: 6 pages, 6 figures, submitted to Annaly Astronomii NowejSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
This research is our forth article related to the topic of cyclic O-C changes, third components as the physical process that cause these changes and elliptical orbits of the third components. Here five more eclipsing binary stars were investigated: EQ Tau, IR Cas, IV Cas, RY Aqr and RZ Com. All of them have cyclic O-C curve with superposition of parabolic trend. We computed the mass transfer rate, minima possible mass of the third component and their errors for each of the researched stars.
- [27] arXiv:1912.12643 [pdf, other]
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Title: Exploiting Morphological Data from Pulsar Wind Nebulae via a Spatio-Temporal Leptonic Transport CodeComments: 13 Pages, 13 Figures. 4 TablesSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
The next era of ground-based Cherenkov telescope development will see a great increase in both quantity and quality of $\gamma$-ray morphological data. This initiated the development of a spatio-temporal leptonic transport code to model pulsar wind nebulae. We present results from this code that predicts the evolution of the leptonic particle spectrum and radiation at different radii in a spherically-symmetric source. We simultaneously fit the overall broadband spectral energy distribution, the surface brightness profile and the X-ray photon index vs.\ radius for PWN 3C~58, PWN G21.5$-$0.9 and PWN G0.9+0.1. Such concurrent fitting of disparate data sets is non-trivial and we thus investigate the utility of different goodness-of-fit statistics, specifically the traditional $\chi^2$ test statistic and a newly developed scaled-flux-normalised test statistic to obtain best-fit parameters. We find reasonable fits to the spatial and spectral data of all three sources, but note some remaining degeneracies that will have to be broken by future observations.
- [28] arXiv:1912.12653 [pdf, other]
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Title: What physics is missing in theoretical models of high-mass stars: new insights from asteroseismologyAuthors: D. M. BowmanComments: 7 pages, 3 figures, invited contribution at the conference "Stars and their variability observed from space - Celebrating the 5th anniversary of BRITE-Constellation", Vienna, Austria, August 19 - 23, 2019. Eds: C. Neiner, W. Weiss, D. Baade, E. Griffin, C. Lovekin, A. MoffatSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
Asteroseismology of massive stars has recently begun a revolution thanks to high-precision time series photometry from space telescopes. This has allowed accurate and robust constraints on interior physical processes, such as mixing and rotation in the near-core region of stars, to be determined across different masses and ages. In this review, I discuss recent advances in our knowledge of massive star interiors made by means of gravity-mode asteroseismology, and highlight some new observational discoveries of variability in some of the most massive stars in our universe.
- [29] arXiv:1912.12679 [pdf, other]
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Title: The tale of the tail -- disentangling the high transverse velocity stars in Gaia DR2Comments: Resubmitted to MNRAS after referee reportSubjects: Astrophysics of Galaxies (astro-ph.GA)
Although the stellar halo accounts for just ~1% of the total stellar mass of the Milky Way, the kinematics of halo stars encode valuable information about the origins and evolution of our Galaxy. It has been shown that the high transverse velocity stars in Gaia DR2 reveal a double sequence in the Hertzsprung-Russell (HR) diagram, indicating a bifurcation in the local stellar halo within 1 kpc. We fit these stars by updating the popular Besan\c{c}on/Galaxia model, incorporating the latest observational results for the stellar halo and an improved kinematic description for the thick-disk from Sch\"onrich & Binney (2012). We are able to obtain a good match to the Gaia data and provide new constraints on the properties of the Galactic disc and stellar halo. In particular, we show that the kinematically defined thick disc contribution to this high velocity tail is ~13%. We look in greater detail using chemistry from LAMOST DR5, identifying a population of retrograde stars with thick-disc chemistry. Our thick disc kinematic model cannot account for this population and so we conclude there is likely to be a contribution from heated or accreted stars in the Solar Neighbourhood. We also investigate proposed dynamical substructures in this sample, concluding that they are probably due to resonant orbits rather than accreted populations. Finally we provide new insights on the nature of the two sequences and their relation with past accretion events and the primordial Galactic disc.
- [30] arXiv:1912.12690 [pdf, other]
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Title: The Splash without a mergerComments: Resubmitted to ApJL after referee reportSubjects: Astrophysics of Galaxies (astro-ph.GA)
The Milky Way's progenitor experienced several merger events which left their imprints on the stellar halo, including the Gaia-Sausage/Enceladus. Recently, it has been proposed that this event perturbed the proto-disk and gave rise to a metal rich ([Fe/H] $>-1$) low angular momentum ($v_{\phi} < 100$ km/s) stellar population. These stars have dynamical and chemical properties different from the accreted stellar halo, but are continuous with the canonical thick disk. In this letter, we use a hydrodynamical simulation of an isolated galaxy which develops clumps that produce a bimodal thin$+$thick disk chemistry to explore whether it forms such a population. We demonstrate clump scattering forms a metal-rich, low angular momentum population, without the need for a major merger. We show that, in the simulation, these stars have chemistry, kinematics and density distribution in good agreement with those in the Milky Way.
- [31] arXiv:1912.12699 [pdf]
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Title: Anticipated Performance of the Square Kilometre Array -- Phase 1 (SKA1)Comments: 27 Pages, 10 Tables, 14 FiguresSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
The Square Kilometre Array (SKA), currently under design, will be a transformational facility for studying the Universe at centimetre and metre wavelengths in the next decade and beyond. This paper provides the current best estimate of the anticipated performance of SKA Phase 1 (SKA1), using detailed design work, before actual on-sky measurements have been made. It will be updated as new information becomes available. The information contained in this paper takes precedent over any previous documents.
- [32] arXiv:1912.12723 [pdf, ps, other]
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Title: Stabilizing effect of magnetic helicity on magnetic cavities in the intergalactic mediumComments: 7 pages, 6 figures. Submitted for publicationSubjects: Astrophysics of Galaxies (astro-ph.GA)
We investigate the effect of magnetic helicity on the stability of buoyant magnetic cavities as found in the intergalactic medium. In these cavities, we insert helical magnetic fields and test whether or not helicity can increase their stability to shredding through the Kelvin-Helmholtz instability and, with that, their lifetime. This is compared to the case of an external vertical magnetic field which is known to reduce the growth rate of the Kelvin-Helmholtz instability. By comparing a low-helicity configuration with a high helicity one with the same magnetic energy we find that an internal helical magnetic field stabilizes the cavity. This effect increases as we increase the helicity content. Stabilizing the cavity with an external magnetic field requires instead a significantly stronger field at higher magnetic energy. We conclude that the presence of helical magnetic fields is a viable mechanism to explain the stability of intergalactic cavities on time scales longer than 100 Myr.
- [33] arXiv:1912.12730 [pdf, ps, other]
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Title: Is Interstellar Object 2I/Borisov a Stardust Comet? Predictions for the Post Perihelion PeriodAuthors: T. Narshall EubanksComments: Submitted to Astrophysical Journal LettersSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
The detection of interstellar bodies passing near the Sun offers the opportunity to observe not just objects similar to those in the solar system, but also unfamiliar objects without solar system analogues. Here I show that Asymptotic Giant Branch (AGB) stellar evolution may lead to the creation, out of stardust, of substantial numbers of nomadic Post-Main-Sequence Objects (PMSOs). ABG nucleosynthesis will produce three broad classes of PMSO chemistry, oxygen, carbon and nitrogen rich (O-rich, C-rich, N-rich, respectively), depending largely on the original stellar mass. I further show that the Interstellar Comet 2I/Borisov (2I) belongs to a kinematic dynamical stream, the Wolf 630 stream, with an age and galactic orbit consistent with its origination as a stardust comet; the apparent lack of water in the 2I coma is consistent with it being a C-rich PMSO. I also provide predictions for distinguishing stardust comets from more conventional interstellar comets and asteroids ejected during planetary formation; these can be applied to 2I in its upcoming observational phase in early 2020 as it moves away from the Sun. In particular, isotope ratios of the CNO elements could be dispositive, IR detection of the 11.3 {\mu}m SiC line, the 30 {\mu}m line, or the IR PAH lines would provide strong evidence for a C-rich PMSO and detection of Na or Li enhancement would indicate an N-rich PMSO.
- [34] arXiv:1912.12782 [pdf, other]
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Title: Commercially fabricated antenna-coupled Transition Edge Sensor bolometer detectors for next generation Cosmic Microwave Background polarimetry experimentAuthors: Aritoki Suzuki, Nicholas Cothard, Adrian T. Lee, Michael D. Niemack, Christopher Raum, Mario Renzullo, Trevor Sasse, Jason Stevens, Patrick Truitt, Eve Vavagiakis, John Vivalda, Benjamin Westrook, Daniel YohannesComments: 7 pages, 5 figures, Proceedings for LTD-18, Accepted for publication in JLTPSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
We report on the development of commercially fabricated multi-chroic antenna coupled Transition Edge Sensor (TES) bolometer arrays for Cosmic Microwave Background (CMB) polarimetry experiments. The orders of magnitude increase in detector count for next-generation CMB experiments requires a new approach in detector wafer production to increase fabrication throughput.
We describe collaborative efforts with a commercial superconductor electronics fabrication facility (SeeQC, Inc.) to fabricate antenna coupled TES bolometer detectors. We have successfully fabricated an operational dual-polarization, dichroic sinuous antenna-coupled TES detector array on a 150 mm diameter wafer. The fabricated detector arrays have average yield of 95\% and excellent uniformity across the wafer. Both RF characteristics and TES bolometer properties are suitable for CMB observations. We successfully fabricated different types of TES bolometers optimized for frequency-multiplexing readout, time-domain multiplexing readout, and microwave SQUID multiplexing readout. We also demonstrated high production throughput. We discuss the motivation, design considerations, fabrication processes, test results, and how industrial detector fabrication could be a path to fabricate hundreds of detector wafers for future CMB polarimetry experiments. - [35] arXiv:1912.12807 [pdf, ps, other]
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Title: A PRESTO-based Parallel Pulsar Search Pipeline Used for FAST Drift Scan DataAuthors: Qiuyu Yu, Zhichen Pan, Lei Qian, Shen Wang, Youling Yue, Menglin Huang, Qiaoli Hao, Shanping You, Bo Peng, Yan Zhu, Lei Zhang, Zhijie LiuComments: 10 pages, 2 figures, accepted by Research in Astronomy and Astrophysics (RAA)Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Astrophysics of Galaxies (astro-ph.GA)
We developed a pulsar search pipeline based on PRESTO (PulsaR Exploration and Search Toolkit). This pipeline simply runs dedispersion, FFT (Fast Fourier Transformation), and acceleration search in process-level parallel to shorten the processing time. With two parallel strategies, the pipeline can highly shorten the processing time in both the normal searches or acceleration searches. This pipeline was first tested with PMPS (Parkes Multibeam Pulsar Survery) data and discovered two new faint pulsars. Then, it was successfully used in processing the FAST (Five-hundred-meter Aperture Spherical radio Telescope) drift scan data with tens of new pulsar discoveries up to now. The pipeline is only CPU-based and can be easily and quickly deployed in computing nodes for testing purposes or data processes.
- [36] arXiv:1912.12813 [pdf, other]
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Title: Probing the full CO spectral line energy distribution (SLED) in the nuclear region of a quasar-starburst system at $z=6.003$Authors: Jianan Li, Ran Wang, Dominik Riechers, Fabian Walter, Roberto Decarli, Bram P. Venamans, Roberto Neri, Yali Shao, Xiaohui Fan, Yu Gao, Chris L. carilli, Alain Omont, Pierre Cox, Karl M. Menten, Jeff Wagg, Frank Bertoldi, Desika NarayananComments: 21 pages, 7 figures, accepted for publication in ApjSubjects: Astrophysics of Galaxies (astro-ph.GA)
We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO $(8-7)$, $(9-8)$, $\rm H_{2}O (2_{0,2}-1_{1,1})$ and $\rm OH^{+} (1_{1}-0_{1})$ and NOrthern Extended Millimeter Array (NOEMA) observations of CO $(5-4)$, $(6-5)$, $(12-11)$ and $(13-12)$ towards the $z = 6.003$ quasar SDSS J231038.88+185519.7, aiming to probe the physical conditions of the molecular gas content of this source. We present the best sampled CO spectral line energy distribution (SLED) at $z = 6.003$, and analyzed it with the radiative transfer code MOLPOP-CEP. Fitting the CO SLED to a one-component model indicates a kinetic temperature $T_{\rm kin} = 228 \ \rm K$, molecular gas density $log (n(\rm H_{2})/\rm cm^{-3}$ )=4.75, and CO column density $log(N(\rm CO)/\rm cm^{-2}) =17.5$, although a two-component model better fits the data. In either case, the CO SLED is dominated by a "warm" and "dense" component. Compared to samples of local (Ultra) Luminous Infrared Galaxies ((U)LIRGs), starburst galaxies and high redshift Submillimeter Galaxies (SMGs), J2310+1855 exhibits higher CO excitation at ($J \geq 8$), like other high redshift quasars. The high CO excitation, together with the enhanced $L_{\rm H_{2}O}/ L_{IR} $, $L_{\rm H_{2}O}/ L_{CO} $ and $L_{OH^{+}}/L_{\rm H_{2}O} $ ratios, suggests that besides the UV radiation from young massive stars, other mechanisms such as shocks, cosmic rays and X-rays might also be responsible for the heating and ionization of the molecular gas. In the nuclear region probed by the molecular emissions lines, any of these mechanisms might be present due to the powerful quasar and the starburst activity.
- [37] arXiv:1912.12840 [pdf, other]
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Title: Cross-Correlation of Far-Infrared Background Anisotropies and CMB Lensing form Herschel and Planck satellitesComments: 12 pages, 10 figures, 3 tablesSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
The cosmic infrared background (CIB) anisotropies and cosmic microwave background (CMB) lensing are powerful measurements for exploring cosmological and astrophysical problems. In this work, we measure the auto-correlation power spectrum of the CIB anisotropies in the Herschel-SPIRE HerMES Large Mode Survey (HeLMS) field, which covers more than 280 square degrees of the sky, and the cross power spectrum between HeLMS CIB and the CMB lensing from Planck. We use the Herschel Level 1 timeline data to merge the CIB maps at 250, 350 and 500 um bands, and mask the areas where the flux is greater than 3-sigma (~50 mJy/beam) or no measured data. We obtain the final CIB power spectra at 100<ell<20,000 by considering several effects, such as beam function, mode coupling, transfer function, and so on. We also calculate the theoretical CIB auto- and cross-power spectra of CIB and CMB lensing by assuming that the CIB emissivity follows Gaussian distribution in redshift. The Markov chain Monte Carlo (MCMC) method is used to perform a joint fit of the CIB auto-power spectra and cross-power spectra of CIB and CMB lensing data. We find that our model can fit the power spectrum data very well, and obtain basically consistent results with higher accuracy comparing to previous studies.
- [38] arXiv:1912.12842 [pdf, ps, other]
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Title: A possible evidence of the gluon condensation effect in cosmic positron and gamma-ray spectraComments: 4 pages, 4 figures, Accepted for publication in the ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph); Nuclear Theory (nucl-th)
The gluon condensation effect in cosmic proton-proton collisions at high energy is used to explain an excess in the positron spectrum observed by AMS. We find that this excess may originate from the GC-effect in Tycho's supernova remnant.
- [39] arXiv:1912.12886 [pdf, other]
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Title: Infrared Properties of Asymptotic Giant Branch Stars in Our Galaxy and the Magellanic CloudsAuthors: Kyung-Won SuhComments: 25 pages, 20 figures, accepted for publication in ApJSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)
We investigate infrared properties of asymptotic giant branch (AGB) stars in our Galaxy and the Magellanic Clouds using various infrared observational data and theoretical models. We use catalogs for the sample of 4996 AGB stars in our Galaxy and about 39,000 AGB stars in the Magellanic Clouds from the available literature. For each object in the sample, we cross-identify the 2MASS, WISE, and Spitzer counterparts. To compare the physical properties of O-rich and C-rich AGB stars in our Galaxy and the Magellanic Clouds, we present IR two color diagrams (2CDs) using various photometric data. We perform radiative transfer model calculations for AGB stars using various possible parameters of central stars and dust shells. Using dust opacity functions of amorphous silicate and amorphous carbon, the theoretical dust shell models can roughly reproduce the observations of AGB stars on various IR 2CDs. Compared with our Galaxy, we find that the Magellanic Clouds are deficient in AGB stars with thick dust shells. Compared with the Large Magellanic Cloud (LMC), the Small Magellanic Cloud (SMC) is more deficient in AGB stars with thick dust shells. This could be because the Magellanic Clouds are more metal poor than our Galaxy and the LMC is more metal rich than the SMC. We also present IR properties of known pulsating variable. Investigating the magnitude distributions at MIR bands for AGB stars in the Magellanic Clouds, we find that the SMC is more deficient in the bright AGB stars at MIR bands compared with the LMC.
- [40] arXiv:1912.12889 [pdf, other]
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Title: Influence of magnetic field on beta-processes in supernova matterComments: 10 pages, 10 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
An influence of a magnetic field on beta-processes is investigated under conditions of a core-collapse supernova. For realistic magnetic fields reachable in astrophysical objects we obtain simple analytical expressions for reaction rates of beta-processes as well as the energy and momentum transferred from neutrinos and antineutrinos to the matter. Based on the results of one-dimensional simulations of a supernova explosion, we found that, in the magnetic field with the strength $B \sim 10^{15}$ G, the quantities considered are modified by several percents only and, as a consequence, the magnetic-field effects can be safely neglected, considering neutrino interaction and propagation in a supernova matter. The analytical results can be also applied for accretion discs formed at a merger of compact objects in close binary systems.
- [41] arXiv:1912.12903 [pdf, other]
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Title: Dark Ultra-Light Scalars and Cosmic Parity ViolationComments: 24 pages, 7 figuresJournal-ref: The Universe 4 (2016) no.4, 29-44Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
If the dark sector of the Universe consists of ultra-light scalars, their coupling to photon via a Chern-Simons term would induce a rotation of the polarization plane of the cosmic microwave background (CMB). This rotation would convert E -mode polarization into B -mode polarization, resulting in new CMB BB correlation and parity-violating TB and EB cross correlations. We review the subject giving details about the derivation of the rotational effects and summarizing the possible signals in current and future CMB B-mode experiments.
- [42] arXiv:1912.12931 [pdf]
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Title: Strong variability of Martian water ice clouds during dust storms revealed from ExoMars Trace Gas Orbiter/NOMADAuthors: Giuliano Liuzzi, Geronimo L. Villanueva, Matteo M. J. Crismani, Michael D. Smith, Michael J. Mumma, Frank Daerden, Shohei Aoki, Ann Carine Vandaele, R. Todd Clancy, Justin Erwin, Ian Thomas, Bojan Ristic, José-Juan Lopez-Moreno, Giancarlo Bellucci, Manish R. PatelComments: Submitted to Journal of Geophysical Research - Planets. 36 pages, 9 figures, 1 tableSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
Observations of water ice clouds and aerosols on Mars can provide important insights into the complexity of the water cycle. Recent observations have indicated an important link between dust activity and the water cycle, as intense dust activity can significantly raise the hygropause, and subsequently increase the escape of water after dissociation in the upper atmosphere. Here present observations from NOMAD/TGO that investigate the variation of water ice clouds in the perihelion season of Mars Year 34 (April 2018-19), their diurnal and seasonal behavior, and the vertical structure and microphysical properties of water ice and dust. These observations reveal the recurrent presence of a layer of mesospheric water ice clouds subsequent to the 2018 Global Dust Storm. We show that this layer rose from 45 to 80 km in altitude on a timescale of days from heating in the lower atmosphere due to the storm. In addition, we demonstrate that there is a strong dawn dusk asymmetry in water ice abundance, related to nighttime nucleation and subsequent daytime sublimation. Water ice particle sizes are retrieved consistently and exhibit sharp vertical gradients (from 0.1 to 4.0 um), as well as mesospheric differences between the Global Dust Storm (<0.5 um) and the 2019 regional dust storm (1.0 um), which suggests differing water ice nucleation efficiencies. These results form the basis to advance our understanding of mesospheric water ice clouds on Mars, and further constrain the interactions between water ice and dust in the middle atmosphere.
- [43] arXiv:1912.12939 [pdf, other]
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Title: Results for the International Pulsar Timing Array Second Mock Data Challenge: New Techniques and Challenges for the Detection of Low-Frequency Gravitational-Wave SignalsAuthors: P. T. Baker, P. R. Brook, W. C. Fiore, N. Garver-Daniels, A. R. Kaiser, M. T. Lam, B. J. Shapiro-Albert, C. A. WittComments: 25 pages, 9 figuresSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
We present a detailed analysis of the International Pulsar Timing Array (IPTA) Second Mock Data Challenge. We tested our analysis methods using the open datasets, and then analyzed the closed datasets. In both the open and the closed datasets, we were able to detect some, but not all, of the injected gravitational wave signals. This work presents two search cases that are not well explored in the pulsar timing array (PTA) literature: a simultaneous search for a stochastic GW background and an individual loud super-massive black hole binary (SMBHB) and a simultaneous search for two SMBHB sources. While we have constructed a cohesive framework for performing these GW searches, our analyses required fine-tuning of the sampling method used in order to appropriately converge. Given the nature of real PTA data in which multiple sources will be present in data, improved techniques will be required in the future to accurately detect and characterize these GW signals.
- [44] arXiv:1912.12965 [pdf, other]
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Title: Kinematic signatures of reverberation mapping of close binaries of supermassive black holes in active galactic nuclei. II. Atlas of two-dimensional transfer functionsComments: 24 pages, 14 figures, accepted by ApJSSubjects: Astrophysics of Galaxies (astro-ph.GA)
Most large galaxies harbor supermassive black holes (SMBHs) in their centers, and galaxies merge. Consequently, binary SMBHs should be common in galactic nuclei. However, close binaries of SMBH (CB-SMBHs) with sub-parsec separation cannot be imaged directly using current facilities. Some indirect signatures, such as periodic signals in light curves and double peaks in emission-line profile, have been used to find CB-SMBH candidates, but ambiguities still exist and no definitive conclusions can be made. We have recently proposed a new method focusing on kinematic signatures that can be derived from reverberation mapping of CB-SMBHs, one that offers a promising avenue to address this important problem. In this paper, we calculated models for a wide range of parameters, but BLRs of two BHs are close but still not merged. The purpose of this supplementary paper is to provide an atlas of two-dimensional transfer functions of CB-SMBHs with a wide range of orbital and geometrical parameters to aid more efficient identification of CB-SMBH candidates in reverberation mapping data.
- [45] arXiv:1912.12967 [pdf, other]
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Title: Multifractal signatures of gravitational waves detected by LIGOComments: 7 pages, 3 figures, proceedings of IAU Symposium 346: High-mass X-ray binaries: illuminating the passage from massive binaries to merging compact objectsSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Data Analysis, Statistics and Probability (physics.data-an)
We analyze the data from the 6 gravitational waves signals detected by LIGO through the lens of multifractal formalism using the MFDMA method, as well as shuffled and surrogate procedures. We identified two regimes of multifractality in the strain measure of the time series by examining long memory and the presence of nonlinearities. The moment used to divide the series into two parts separates these two regimes and can be interpreted as the moment of collision between the black holes. An empirical relationship between the variation in left side diversity and the chirp mass of each event was also determined.
- [46] arXiv:1912.12977 [pdf, other]
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Title: Preheating in radiative corrections to $φ^4$ inflation with non-minimal coupling in Palatini formulationAuthors: Nilay BostanComments: 11 pages, 1 figureSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
We discuss the impact of the preheating stage in radiative corrections due to interaction of the inflaton to fermions to $\phi^4$ inflation with non-minimal coupling in Palatini formulation. In Palatini inflation with large non-minimal coupling the field is allow to return to the plateau region during the reheating stage, so the average equation of state per oscillations is closer to $-1$ than to $1/3$. The incursion in the plateau leads, however, to a highly efficient tachyonic instability able to reheat the Universe in less than one e-fold. By taking into account prescription II discussed in the literature, in the wide range of $\kappa-\xi$, we figure out spectral index $n_s$ and tensor-to-scalar ratio $r$ which are compatible with the data given by the Keck Array/BICEP2 and Planck collaborations.
- [47] arXiv:1912.12990 [pdf, other]
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Title: Correcting the effect of magnetic tongues on the tilt angle of bipolar active regionsSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
The magnetic polarities of bipolar active regions (ARs) exhibit elongations in line-of-sight magnetograms during their emergence. These elongations are referred to as magnetic tongues and attributed to the presence of twist in the emerging magnetic flux-ropes (FRs) that form ARs. The presence of magnetic tongues affects the measurement of any AR characteristic that depends on its magnetic flux distribution. The AR tilt-angle is one of them. We aim to develop a method to isolate and remove the flux associated with the tongues to determine the AR tilt-angle with as much precision as possible. As a first approach, we used a simple emergence model of a FR. This allowed us to develop and test our aim based on a method to remove the effects of magnetic tongues. Then, using the experience gained from the analysis of the model, we applied our method to photospheric observations of bipolar ARs that show clear magnetic tongues. Using the developed procedure on the FR model, we can reduce the deviation in the tilt estimation by more than 60%. Next we illustrate the performance of the method with four examples of bipolar ARs selected for their large magnetic tongues. The new method efficiently removes the spurious rotation of the bipole. This correction is mostly independent of the method input parameters and significant since it is larger than all the estimated tilt errors. We have developed a method to isolate the magnetic flux associated with the FR core during the emergence of bipolar ARs. This allows us to compute the AR tilt-angle and its evolution as precisely as possible. We suggest that the high dispersion observed in the determination of AR tilt-angles in studies that massively compute them from line-of sight magnetograms can be partly due to the existence of magnetic tongues whose presence is not sufficiently acknowledged.
- [48] arXiv:1912.12994 [pdf, other]
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Title: Be and Bn stars: Balmer discontinuity and stellar-class relationshipAuthors: Y. R. Cochetti, J. Zorec, L. S. Cidale, M. L. Arias, Y. Aidelman, A. F. Torres, Y. Frémat, A. GranadaComments: 30 pages, 9 tables, 19 figures. Accepted for publication in A&ASubjects: Solar and Stellar Astrophysics (astro-ph.SR)
A significant number of Be stars show a second Balmer discontinuity (sBD) attributed to an extended circumstellar envelope (CE). The fast rotational velocity of Be stars undoubtedly plays a significant role in the formation of the CE. However, Bn stars, which are also B-type rapidly rotating stars, do not all present clear evidence of being surrounded by circumstellar material. We aim to characterize the populations of Be and Bn stars, and discuss the appearance of the sBD as a function of the stellar parameters. We expect to find new indices characterizing the properties of CEs in Be stars and properties relating Be and Bn stars. Correlations of the aspect and intensity of the sBD and the emission in the H$\alpha$ line with the stellar parameters and the $V\!\sin i$ are presented. Some Bn stars exhibit the sBD in absorption, which may indicate the presence of rather dense CEs. Six Bn stars show emission in the H$\alpha$ line, so they are reclassified as Be stars. The sBD in emission appears in Be stars with $V\!\sin i \lesssim 250$ km\,s$^{-1}$, and in absorption in both Be and Bn stars with \mbox{$V\!\sin i \gtrsim 50$ km\,s$^{-1}$}. Low-mass Be and Bn stars share the same region in the Hertzsprung-Russell diagram. The distributions of rotational to critical velocity ratios of Be and Bn stars corresponding to the current stellar evolutionary stage are similar, while distributions inferred for the zero-age main sequence have different skewness. We found emission in the H$\alpha$ line and signs of a CE in some Bn stars, which motivated us to think that Bn and Be stars probably belong to the same population. It should be noted that some of the most massive Bn stars could display the Be phenomenon at any time. The similarities found among Be and Bn stars deserve to be more deeply pursued.
- [49] arXiv:1912.13026 [pdf, ps, other]
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Title: The skewness of z=0.5 redshift-space galaxy distribution in Modified GravityAuthors: Wojciech A. HellwingComments: 8 pages, 4 figures, proceedings from the XXXIX-th general assembly of the Polish Astronomical Society, September 2019, Olsztyn, PolandSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
We study the reduced skewness, $S_{3,g}\equiv\bar{\xi}_{3,g}/\bar{\xi}_{2,g}^2$ of galaxy distribution at $z=0.5$ in two families of modfied gravity models: the Hu-Sawicki $f(R)$-gravity and normal-branch of Dvali-Gabadadze-Porrati (nDGP) models. We use a set of mock galaxy catalogues specifally designed to match CMASS spectroscopic galaxy sample. For the first time we investigate the third reduced moment of such galaxy distributions both in the redshift space. Our analysis confirms that the signal previously indicated only for dark matter halo catalogues persists also in realistic mock galaxy samples. % Furthermore, we study the magnitude of the redshift-space distortions (RSD) % induce onto the reduced skewness of all models and show that RSD have a similar impact separately on $\bar{\xi}_{3,g}$ and on $\bar{\xi}_{2,g}^2$ terms. Our analysis offers a possibility to extract a potential modified gravity signal in $S_3$ from spectroscopic galaxy data without a need for a very precise and self-consistent RSD models constructed for each and every modified gravity scenario separately. We show that the relative deviations from \lcdm $S_{3,g}$ of various modified gravity models can vary from $7$ down to $\sim 2-3\%$ effects. Albeit, the effect looks small, we show that for considered models it can foster a $2-3\sigma$ falsification. Finally we argue that galaxy sample of a significantly higher number density should provide even stronger constraints by limiting shot-noise effects affecting the $S_{3,g}$ estimates at small comoving separati
- [50] arXiv:1912.13034 [pdf, other]
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Title: From matter to galaxies: General relativistic bias for the one-loop bispectrumComments: 24 pages, 3 FiguresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
We write down the Lagrangian bias expansion in general relativity up to 4th order in terms of operators describing the curvature of an early-time hypersurface for comoving observers. They can be easily expanded in synchronous or comoving gauges. This is necessary for the computation of the one-loop halo bispectrum, where relativistic effects can be degenerate with a primordial non-Gaussian signal. Since the bispectrum couples scales, an accurate prediction of the squeezed limit behavior needs to be both non-linear and relativistic. We then evolve the Lagrangian bias operators in time in comoving gauge, obtaining non-local operators analogous to what is known in the Newtonian limit. Finally, we show how to renormalize the bias expansion at an arbitrary time and find that this is crucial in order to cancel unphysical $1/k^2$ divergences in the large-scale power spectrum and bispectrum that could be mistaken for a contamination to the non-Gaussian signal.
- [51] arXiv:1912.13049 [pdf]
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Title: A Probabilistic Case For A Large Missing Carbon Sink On Mars After 3.5 Billion Years AgoJournal-ref: HEarth Planet. Sci. Lett. 116001 (2019)Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Mars has a thin (6 mbar) CO2 atmosphere currently. There is strong evidence for paleolakes and rivers formed by warm climates on Mars, including after 3.5 billion years (Ga) ago, which indicates that a CO2 atmosphere thick enough to permit a warm climate was present at these times. Since Mars no longer has a thick CO2 atmosphere, it must have been lost. One possibility is that Martian CO2 was lost to space. Oxygen escape rates from Mars are high enough to account for loss of a thick CO2 atmosphere, if CO2 was the main source of escaping O. But here, using H isotope ratios, O escape calculations, and quantification of the surface O sinks on Mars, we show for the first time that O escape from Mars after 3.5 Ga must have been predominantly associated with the loss of H2O, not CO2, and therefore it is unlikely that >250 mbar Martian CO2 has been lost to space in the last 3.5 Ga, because such results require highly unfavored O loss scenarios. It is possible that the presence of young rivers and lakes on Mars could be reconciled with limited CO2 loss to space if crater chronologies on Mars are sufficiently incorrect that all apparently young rivers and lakes are actually older than 3.5 Ga, or if climate solutions exist for sustained runoff on Mars with atmospheric CO2 pressure <250 mbar. However, our preferred solution to reconcile the presence of <3.5 Gya rivers and lakes on Mars with the limited potential for CO2 loss to space is a large, as yet undiscovered, geological C sink on Mars.
- [52] arXiv:1912.13096 [pdf]
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Title: Computer Modeling of Irregularly Spaced Signals. Statistical Properties of the Wavelet Approximation Using a Compact Weight FunctionComments: "Annaly Astronomii Nowej" (accepted)Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
The algorithm of modified wavelet analysis is discussed. It is based on the weighted least squares approximation. Contrary to the Gaussian as a weight function, we propose to use a compact weight function. The accuracy estimates using the statistically correct expressions for the least squares approximations with an additional weight function are compared with that obtained using the bootstrap method.
- [53] arXiv:1912.13112 [pdf, ps, other]
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Title: Observation of the second LIGO/Virgo event connected with binary neutron star merger S190425z in the gamma-ray rangeAuthors: A.S. Pozanenko (1,2), P.Yu. Minaev (1), S.A. Grebenev (1), I.V. Chelovekov (1) ((1) Space Research Institute, Russian Academy of Sciences, (2) National Research University "High School of Economics")Comments: 16 pages, 7 figures, 2 tablesSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
Observations of the gravitational-wave (GW) event S190425z registered by the LIGO/Virgo detectors with the Anti-Coincidence Shield (ACS) of the gamma-ray spectrometer SPI aboard the INTEGRAL observatory are presented. With a high probability (>99%) it was associated with a neutron star (NS) merger in a close binary system. This is only the second event of such type in the history of GW observations (after GW170817). A weak gamma-ray burst, GRB190425, consisting of two pulses in ~0.5 and ~5.9 s after the NS merging in S190425z was detected by SPI-ACS. The pulses had a priori reliability of 3.5 and 4.4 sigma as single events and 5.5 sigma as a combined event. Analysis of the SPI-ACS count rate history recorded these days (~125 ks in total) has shown that the rate of appearance of two close pulses with characteristics of GRB190425 by chance does not exceed 6.4 x 10^{-5} s^{-1}. We note that the time profile of GRB190425 has a lot in common with the profile of the GRB170817A burst accompanying the GW170817 event; that both the NS mergers were the closest (<150 Mpc) of all the events registered by the LIGO/Virgo detectors; and that there were no confident excesses of gamma-ray emission over the background detected in any of >30 black hole merger events recorded to the moment by these detectors. No hard X-ray flares were detected in the field of view of the SPI and IBIS-ISGRI gamma-ray telescopes aboard INTEGRAL. This, as well as the lack of detection of gamma-ray emission from GRB190425 by the GBM monitor of the Fermi observatory assuming its occultation by the Earth, can significantly reduce the localization area for the source of this GW event. The estimates of the parameters E_{iso} and E_{p} for GRB190425 are obtained and compared with the similar parameters for GRB170817A.
- [54] arXiv:1912.13130 [pdf]
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Title: Production of nitric oxide by a fragmenting bolide: An exploratory numerical studyComments: 30 pages, 9 figuresJournal-ref: Mathematical Methods in Applied Sciences (2019)Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Computational Physics (physics.comp-ph)
A meteoroid's hypersonic passage through the Earth's atmosphere results in ablational and fragmentational mass loss. Potential shock waves associated with a parent object as well as its fragments can modify the surrounding atmosphere and produce a range of physico-chemical effects. Some of the thermally driven chemical and physical processes induced by meteoroid-fragment generated shock waves, such as nitric oxide (NO) production, are less understood. Any estimates of meteoric NO production depend not only on a quantifiable meteoroid population and a rate of fragmentation, with a size capable of producing high temperature flows, but also on understanding the physical properties of the meteor flows along with their thermal history. We performed an exploratory pilot numerical study using ANSYS Fluent, the CFD code, to investigate the production of NO in the upper atmosphere by small meteoroids (or fragments of meteoroids after they undergo a disruption episode) in the size range from 10-2 m to 1 m. Our model uses the simulation of a spherical body in the continuum flow at 70 and 80 km altitude to approximate the behaviour of a small meteoroid capable of producing NO. The results presented in this exploratory study are in good agreement with previous studies.
- [55] arXiv:1912.13135 [pdf, other]
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Title: Searches for neutrinos from cosmic-ray interactions in the Sun using seven years of IceCube dataAuthors: IceCube Collaboration: M. G. Aartsen, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, C. Alispach, K. Andeen, T. Anderson, I. Ansseau, G. Anton, C. Argüelles, J. Auffenberg, S. Axani, P. Backes, H. Bagherpour, X. Bai, A. Balagopal V., A. Barbano, S. W. Barwick, B. Bastian, V. Baum, S. Baur, R. Bay, J. J. Beatty, K.-H. Becker, J. Becker Tjus, S. BenZvi, D. Berley, E. Bernardini, D. Z. Besson, G. Binder, D. Bindig, E. Blaufuss, S. Blot, C. Bohm, S. Böser, O. Botner, J. Böttcher, E. Bourbeau, J. Bourbeau, F. Bradascio, J. Braun, S. Bron, J. Brostean-Kaiser, A. Burgman, J. Buscher, R. S. Busse, T. Carver, C. Chen, E. Cheung, D. Chirkin, S. Choi, K. Clark, L. Classen, A. Coleman, G. H. Collin, J. M. Conrad, P. Coppin, P. Correa, D. F. Cowen, R. Cross, P. Dave, C. De Clercq, et al. (297 additional authors not shown)Comments: 25 pages, 8 figuresSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
Cosmic-ray interactions with the solar atmosphere are expected to produce particle showers which in turn produce neutrinos from weak decays of mesons. These solar atmospheric neutrinos (SA$\nu$s) have never been observed experimentally. A detection would be an important step in understanding cosmic-ray propagation in the inner solar system and the dynamics of solar magnetic fields. SA$\nu$s also represent an irreducible background to solar dark matter searches and a detection would allow precise characterization of this background. Here, we present the first experimental search based on seven years of data collected from May 2010 to May 2017 in the austral winter with the IceCube Neutrino Observatory. An unbinned likelihood analysis is performed for events reconstructed within 5 degrees of the center of the Sun. No evidence for a SA$\nu$ flux is observed. After inclusion of systematic uncertainties, we set a 90\% upper limit of $1.02^{+0.20}_{-0.18}\cdot10^{-13}$~$\mathrm{GeV^{-1}cm^{-2}s^{-1}}$ at 1 TeV.
- [56] arXiv:1912.13173 [pdf, other]
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Title: Measurements of the low energy neutron and gamma ray accompaniment of extensive air showers in the knee region of primary cosmic ray spectrumAuthors: A. Shepetov, A. Chubenko, B. Iskhakov, O. Kryakunova, O. Kalikulov, S. Mamina, K. Mukashev, V. Piscal, V. Ryabov, N. Saduyev, T. Sadykov, N. Salikhov, E. Tautaev, L. Vil'danova, V. ZhukovComments: 23 pages, 14 figures. Submitted to European Physical Journal PlusSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM)
Purposeful investigation of radiation fluxes strongly delayed in relation to the main particles front of extensive air shower (EAS) was undertaken at the Tien Shan Mountain Cosmic Ray Station. It was found that the passage of the EAS can be accompanied by the delayed thermal neutrons and by the soft $(30-50)$ keV gamma rays, mostly concentrated within a region of about $(5-10)$ m around shower axis, where the integral radiation fluence can vary in the limits of $(10^{-4}-1)$ cm$^{-2}$ for neutrons, and of $(0.1-1000)$ cm$^{-2}$ for gamma rays. The dependence of signal multiplicity on the shower size $N_e$ has a power shape both for the neutron and gamma ray components, with a sharp increase of its power index around the value of $N_e\approx 10^6$, which corresponds to the position of the $3\cdot10^{15}$ eV knee in the primary cosmic ray spectrum. Total duration of detectable radiation signal after the EAS passage can be of some tens of milliseconds in the case of neutron component, and up to a few whole seconds for gamma rays. The delayed accompaniment of low-energy radiation particles can be an effective probe to study the interaction of the hadronic component of EAS.
- [57] arXiv:1912.13178 [pdf, ps, other]
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Title: The growth of bulges and discs in relatively HI-rich galaxies: indication from HI scaling relationsComments: Accepted by MNRAS, 13 pages, 9 figuresSubjects: Astrophysics of Galaxies (astro-ph.GA)
We study the relation between the properties of the bulge/disc components and the HI mass fraction of galaxies. We find that at fixed stellar mass, disc colours are correlated with the HI mass fraction, while bulge colours are not. The lack of a correlation between the bulge colour and the HI mass fraction is regardless whether the bulges are pseudo, or whether the galaxies host bars or are interacting with a neighbour. There is no strong correlation between the colours of the discs and bulges either. These results suggest that the current total amount of HI is closely related to the formation of discs, but does not necessarily fuel the formation of (pseudo) bulges in an efficient way. We do not find evidence for the star formation in the discs to be quenched by the bulges.
- [58] arXiv:1912.13198 [pdf, other]
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Title: The Morphological, Elastic, and Electric Properties of Dust Aggregates in Comets: A Close Look at COSIMA/Rosetta's Data on Dust in Comet 67P/Churyumov-GerasimenkoComments: 17 pages, 12 figures, 1 tables, to appear in Planetary and Space ScienceSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
The Cometary Secondary Ion Mass Analyzer (COSIMA) onboard ESA's Rosetta orbiter has revealed that dust particles in the coma of Comet 67P/Churyumov-Gerasimenko are aggregates of small grains. We study the morphological, elastic, and electric properties of dust aggregates in the coma of Comet 67P/Churyumov-Gerasimenko using optical microscopic images taken by the COSIMA instrument. Dust aggregates in COSIMA images are well represented as fractals in harmony with morphological data from MIDAS (Micro-Imaging Dust Analysis System) and GIADA (Grain Impact Analyzer and Dust Accumulator) onboard Rosetta. COSIMA's images, together with the data from the other Rosetta's instruments such as MIDAS and GIADA do not contradict the so-called rainout growth of $10~\mu\mathrm{m}$-sized particles in the solar nebula. The elastic and electric properties of dust aggregates measured by COSIMA suggest that the surface chemistry of cometary dust is well represented as carbonaceous matter rather than silicates or ices, consistent with the mass spectra, and that organic matter is to some extent carbonized by solar radiation, as inferred from optical and infrared observations of various comets. Electrostatic lofting of cometary dust by intense electric fields at the terminator of its parent comet is unlikely, unless the surface chemistry of the dust changes from a dielectric to a conductor. Our findings are not in conflict with our current understanding of comet formation and evolution, which begin with the accumulation of condensates in the solar nebula and follow with the formation of a dust mantle in the inner solar system.
- [59] arXiv:1912.13208 [pdf, other]
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Title: Cosmological consequences of a scalar field with oscillating equation of state: A possible solution to the fine-tuning and coincidence problemsAuthors: S. X. TianComments: 5 pages, 3 figures, submitted to PRDSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
We propose a new dark energy model for solving the cosmological fine-tuning and coincidence problems. The key idea is that the Universe may have several acceleration phases across the history. The specific example we study is a quintessence model with repeated approximately double exponential potential, which only introduces one Planck scale parameter and three dimensionless parameters of order unity. The cosmological background evolution equations can be recast into a four-dimensional dynamical system. The main properties of this system are discussed in details. As a bonus, our model provides a natural unification of early inflation, late-time dark energy and early dark energy recently proposed to ease the Hubble tension.
- [60] arXiv:1912.13209 [pdf, other]
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Title: Accrete, Accrete, Accrete... Bang! (and repeat): The Remarkable Recurrent NovaeAuthors: Matthew J. DarnleyComments: A review article to appear within The Golden Age of Cataclysmic Variables and Related Objects V, Proceedings of Science. 19 pages, 2 figures, 1 tableSubjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)
All novae recur, but only a handful have been observed in eruption more than once. These systems, the recurrent novae (RNe), are among the most extreme examples of novae. RNe have long been thought of as potential type Ia supernova progenitors, and their claim to this 'accolade' has recently been strengthened. In this short review RNe will be presented within the framework of the maximum magnitude-rate of decline (MMRD) phase-space. Recent work integrating He-flashes into nova models, and the subsequent growth of the white dwarf, will be explored. This review also presents an overview of the Galactic and extragalactic populations of RNe, including the newly identified 'rapid recurrent nova' subset - those with recurrence periods of ten years, or less. The most exciting nova system yet discovered - M31N 2008-12a, with its annual eruptions and vast nova super-remnant, is introduced. Throughout, open questions regarding RNe, and some of the expected challenges and opportunities that the near future will bring are addressed.
- [61] arXiv:1912.13215 [pdf, other]
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Title: A NuSTAR View of GRS 1716$-$249 in the Hard and Intermediate StatesComments: 10 pages, 7 figures, accepted by MNRASSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
We present a detailed analysis of the spectral properties of the black hole transient GRS 1716-249, based on the archival Swift and NuSTAR observations taken during the outburst of this source in 2016-2017. The first six NuSTAR observations show that the source is in a canonical hard state, where the spectrum is dominated by a power-law continuum. The seventh NuSTAR observation is taken during the intermediate state where both a disc thermal component and a power-law continuum are shown. All of our observations show a broad emission line feature in the iron band and a Compton hump above 10 keV. We model the broad band spectra using a high density disc reflection model, where the soft X-ray emission in the hard state is interpreted as part of the disc reflection component. This model enables us to constrain the disc density parameter of GRS 1716-249 in the range of $10^{19}$-$10^{20}$ cm$^{-3}$. We only obtain an upper limit of the inner disc radius using high density disc reflection spectroscopy and the results indicate either a non-truncated disc or a slightly truncated disc with $R_{\rm in}<20r_{\rm g}$.
- [62] arXiv:1912.13223 [pdf, ps, other]
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Title: Magnetic field dependence of bipolar magnetic region tilts on the Sun: Indication of tilt quenchingComments: 7 pages and 4 figures; Accepted for Publication in ApJLSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
The tilt of bipolar magnetic region (BMR) is crucial in the Babcock--Leighton process for the generation of the poloidal magnetic field in Sun. Based on the thin flux tube model of the BMR formation, the tilt is believed to be caused by the Coriolis force acting on the rising flux tube of the strong toroidal magnetic field from the base of the convection zone (BCZ). We analyze the magnetic field dependence of BMR tilts using the magnetograms of Michelson Doppler Imager (MDI) (1996-2011) and Helioseismic and Magnetic Imager (HMI) (2010-2018). We observe that the distribution of the maximum magnetic field ($B_{\rm max}$) of BMRs is bimodal. Its first peak at the low field corresponds to BMRs which do not have sunspots as counterparts in the white light images, whereas the second peak corresponds to sunspots as recorded in both types of images. We find that the slope of Joy's law ($\gamma_0$) initially increases slowly with the increase of $B_{\rm max}$. However, when $B_{\rm max} \gtrsim 2$ kG, $\gamma_0$ decreases. Scatter of BMR tilt around Joy's law systematically decreases with the increase of $B_{\rm max}$. The decrease of observed $\gamma_0$ with $B_{\rm max}$ provides a hint to a nonlinear tilt quenching in the Babcock--Leighton process. We finally discuss how our results may be used to make a connection with the thin flux tube model.
- [63] arXiv:1912.13240 [pdf, ps, other]
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Title: ALMA observations reveal no preferred outflow--filament and outflow--magnetic field orientationsAuthors: T. Baug, Ke Wang, Tie Liu, Mengyao Tang, Qizhou Zhang, Di Li, Eswaraiah Chakali, Sheng-Yuan Liu, Anandmayee Tej, Paul F. Goldsmith, Leonardo Bronfman, Sheng-Li Qin, Viktor L. Toth, Pak-Shing Li, Kee-Tae KimComments: 18 pages, 2 tables, 6 figures (3 additional figures in Appendix); Accepted for publication in the Astrophysical JournalSubjects: Astrophysics of Galaxies (astro-ph.GA)
We present a statistical study on the orientation of outflows with respect to large-scale filaments and the magnetic fields. Although filaments are widely observed toward Galactic star-forming regions, the exact role of filaments in star formation is unclear. Studies toward low-mass star-forming regions revealed both preferred and random orientation of outflows respective to the filament long-axes, while outflows in massive star-forming regions mostly oriented perpendicular to the host filaments, and parallel to the magnetic fields at similar physical scales. Here, we explore outflows in a sample of 11 protoclusters in HII regions, a more evolved stage compared to IRDCs, using ALMA CO (3-2) line observations. We identify a total of 105 outflow lobes in these protoclusters. Among the 11 targets, 7 are embedded within parsec-scale filamentary structures detected in $^{13}$CO line and 870 $\mu m$ continuum emissions. The angles between outflow axes and corresponding filaments ($\gamma_\mathrm{Fil}$) do not show any hint of preferred orientations (i.e., orthogonal or parallel as inferred in numerical models) with respect to the position angle of the filaments. Identified outflow lobes are also not correlated with the magnetic fields and Galactic plane position angles. Outflows associated with filaments aligned along the large-scale magnetic fields are also randomly orientated. Our study presents the first statistical results of outflow orientation respective to large-scale filaments and magnetic fields in evolved massive star-forming regions. The random distribution suggests a lack of alignment of outflows with filaments, which may be a result of the evolutionary stage of the clusters.
- [64] arXiv:1912.13281 [pdf, other]
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Title: Search for 7Be in the outburst of four recent novaeAuthors: Paolo Molaro, Luca Izzo, Piercarlo Bonifacio, Margarita Hernanz, Pierluigi Selvelli, Massimo Della ValleComments: 13 pages, 12 figures, accepted MNRASSubjects: Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
Following the recent detection of 7Be in the outburst spectra of Classical Novae we report the search for this isotope in the outbursts of four recent bright novae by means of high resolution UVES observations. The 7BeII 313.0583, 313.1228 nm doublet resonance lines are detected in the high velocity components of Nova Mus 2018 and ASASSN-18fv during outburst. On the other hand 7BeII is neither detected in ASASSN-17hx and possibly nor in Nova Cir 2018, therefore showing that the 7BeII is not always ejected in the thermonuclear runaway. Taking into account the 7Be decay we find X(7Be)/X(H) approx 1.5 x10 ^{-5} and 2.2 x 10 ^{-5} in Nova Mus 2018 and ASASSN-18fv, respectively. A value of 7Be/H about 2 x10 ^{-5} is found in 5 out of the 7 extant measurements and it might be considered as a typical 7Be yield for novae. However, this value is almost one order of magnitude larger than predicted by current theoretical models. We argue that the variety of high 7Be/H abundances could be originated in a higher than solar content of 3He in the donor star. The cases with 7Be not detected might be related to a small mass of the WD or to relatively little mixing with the core material of the WD. The 7Be /H, or 7Li/H, abundance is about 4 dex above meteoritic thus confirming the novae as the main sources of 7Li in the Milky Way.
- [65] arXiv:1912.13316 [pdf, other]
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Title: MIRACLES: atmospheric characterization of directly imaged planets and substellar companions at 4-5 micron. I. Photometric analysis of $β$ Pic b, HIP 65426 b, PZ Tel B and HD 206893 BAuthors: Tomas Stolker, Sascha P. Quanz, Kamen O. Todorov, Jonas Kühn, Paul Mollière, Michael R. Meyer, Thayne Currie, Sebastian Daemgen, Baptiste LavieComments: 25 pages, 15 figures, submitted to A&ASubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Directly imaged planets and substellar companions are key targets for the characterization of self-luminous atmospheres. Their photometric appearance at 4-5 $\mu$m is sensitive to the chemical composition and cloud content of their atmosphere. We aim at systematically characterizing the atmospheres of directly imaged low-mass companions at 4-5 $\mu$m. We want to homogeneously process the data and compile a photometric library at thermal wavelengths of these mostly young, low-gravity objects. In this way, we want to find trends related to their spectral type and surface gravity by comparing with isolated brown dwarfs and predictions from atmospheric models. We have used the high-resolution, high-contrast capabilities of NACO at the VLT to directly image the companions of HIP 65426, PZ Tel, and HD 206893 in the NB4.05 and/or $M'$ filters. For the same targets, and additionally $\beta$ Pic, we have also analyzed six archival VLT/NACO datasets which were taken with the NB3.74, $L'$, NB4.05, and $M'$ filters. The $L'$-NB4.05 and $L'$-$M'$ colors of the studied sample are all red while the NB4.05-$M'$ color is blue for $\beta$ Pic b, gray for PZ Tel B, and red for HIP 65426 b and HD 206893 B (although typically with low significance). The absolute NB4.05 and $M'$ fluxes of our sample are all larger than those of field dwarfs with similar spectral types. Finally, the surface gravity of $\beta$ Pic b has been constrained to $\log{g} = 4.17_{-0.13}^{+0.10}$ dex from its photometry and dynamical mass. A red color at 3-4 $\mu$m and a blue color at 4-5 $\mu$m might be (partially) caused by H$_2$O and CO absorption, respectively. The red characteristics of $\beta$ Pic b, HIP 65426 b, and HD 206893 B at 3-5$\mu$m, as well as their higher fluxes in NB4.05 and $M'$ compared to field dwarfs, indicate that cloud densities are enhanced close to the photosphere as a result of their low surface gravity.
- [66] arXiv:1912.13326 [pdf, other]
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Title: EFT Compatible PBHs: Effective Spawning of the Seeds for Primordial Black Holes during InflationComments: 1+18 pages, 5 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
Most of the inflationary scenarios that try to explain the origin of Primordial Black Holes (PBHs) from the enhancements of the power spectrum to values of order one at the relevant scales, run into clashes with the Effective Field Theory (EFT) criteria or fail to enhance the power spectrum to such large amplitudes. In this paper, we unravel a mechanism of enhancing the power spectrum during inflation without flattening the potential or reducing the sound speed of scalar perturbations. The mechanism is based on this observation in the formalism of Extended EFT of inflation (EEFToI) with the sixth order polynomial dispersion relation for scalar perturbations, that if the quartic coefficient in the dispersion relation is negative and smaller than a certain threshold, the amplitude of power spectrum can be enhanced substantially. The instability mechanism needs to be arranged to kick in at the scales of interest which is related to the mass of the PBHs one would like to produce, which can be ten(s) of solar mass PBHs, suitable for LIGO events, or $10^{-13}-10^{-17}$ solar mass PBHs, which can comprise the whole dark matter energy density. This can be accommodated within the EEFToI by endowing time-dependence to the coefficients of the dispersion relation, or in turn, to the couplings in the unitary gauge action. We argue that for the range of parameters that the mechanisms enhance the power spectrum to the required amount, the strong coupling is avoided.
- [67] arXiv:1912.13352 [pdf, ps, other]
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Title: Radio study of the extended TeV source VER J1907+062Comments: Accepted for publicacion in MNRAS. Preprint versionSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
This paper aims to provide new insights on the origin of the TeV source VER J1907+062 through new high-quality radio observations. We used the Karl G. Jansky Very Large Array (VLA) to observe the whole extension of VER J1907+062 at 1.5 GHz with a mosaicking technique and the PSR J1907+0602 in a single pointing at 6 GHz. These data were used together with $^{12}$CO and atomic hydrogen observations obtained from public surveys to investigate the interstellar medium in the direction of VER J1907+062. The new radio observations do not show any evidence of a pulsar wind nebula (PWN) driven by the pulsars present in the field and no radio counterpart to the proposed X-ray PWN powered by PSR J1907+0602 is seen in the new VLA image at 6 GHz down to a noise level of 10 $\mu$Jy/beam. Molecular clouds were discovered over the eastern, southern, and western borders of the radio shell of G40.5$-$0.5, suggesting an association with this supernova remnant. We explored several scenarios for the origin of VER J1907+062. We propose as the most probable scenario one in which the TeV emission is produced by two separated gamma-ray sources located at different distances: one of leptonic origin and associated with a PWN powered by PSR J1907+0602 at $\sim 3.2$ kpc and another of hadronic origin and produced by the interaction between G40.5$-$0.5 and the surrounding molecular gas at $\sim 8.7$ kpc.
- [68] arXiv:1912.13354 [pdf, other]
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Title: Underground neutron events at Tien Shan and the properties of the $10^{14}-10^{17}$ eV EAS muonic componentAuthors: A.Shepetov, A.Chubenko, O.Kryakunova, O.Kalikulov, S.Mamina, K.Mukashev, R.Nam, V.Piscal, V.Ryabov, T.Sadykov, N.Saduev, N.Salikhov, E.Tautaev, L.Vildanova, Zh.Zhantayev, V.ZhukovComments: 7 pages, 5 figures. Sent to Journal of Physics: Conference SeriesJournal-ref: J. Phys.: Conf. Ser. 1181 (2019) 012017Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM)
The events of multiple neutron production under 2000g/cm$^2$ thick rock absorber were studied at the Tien~Shan mountain cosmic ray station, at the altitude of 3340m above the sea level. From comparison of the experimental and Geant4 simulated neutron multiplicity spectra it follows that the great bulk of these events can be explained by interaction of cosmic ray muons with internal material of the neutron detector. In synchronous operation of the underground neutron monitor with the Tien~Shan shower detector system it was found that the characteristics of the muonic component of extensive air showers which is seemingly responsible for generation of the neutron events underground do change noticeably within the energy range of the knee of primary cosmic ray spectrum. Some peculiar shower events were detected when the neutron signal reveals itself only $\sim$(100--1000)\,$\mu$s after the passage of the shower particles front which probably means an existence of corresponding delay of the muon flux in such events.
- [69] arXiv:1912.13356 [pdf, other]
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Title: New complex EAS installation of the Tien Shan Mountain Cosmic Ray StationAuthors: A.P.Chubenko, A.L.Shepetov, V.P.Antonova, R.U.Beisembayev, A.S.Borisov, O.D.Dalkarov, O.N.Kryakunova, K.M.Mukashev, R.A.Mukhamedshin, R.A.Nam, N.F.Nikolaevsky, V.P.Pavlyuchenko, V.V.Piscal, V.S.Puchkov, V.A.Ryabov, T.Kh.Sadykov, N.O.Saduev, N.M.Salikhov, S.B.Shaulov, A.V.Stepanov, N.G.Vildanov, L.I.Vildanova, M.I.Vildanova, N.N.Zastrozhnova, V.V.ZhukovComments: 32 pages, 20 figures. Submitted to Nucl. Instrum. Methods AJournal-ref: Nucl. Instrum. Methods A 832 (2016) 158-178Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM); Instrumentation and Detectors (physics.ins-det)
We present a description of the new complex installation for the study of extensive air showers which was created at the Tien Shan mountain cosmic ray station, as well as the results of the test measurements made there in 2014-2016. At present, the system for registration of electromagnetic shower component consists of $\sim$100 detector points built on the basis of plastic scintillator plates with the sensitive area of 0.25m$^2$ and 1m$^2$, spread equidistantly over $\sim$10$^4$m$^2$ space. The dynamic range of scintillation amplitude measurements is currently about $(3-7)\cdot 10^4$, and there is a prospect of it being extended up to $\sim$10$^6$. The direction of shower arrival is defined by signal delays from a number of the scintillators placed cross-wise at the periphery of the detector system. For the investigation of nuclear active shower components there was created a multi-tier 55m$^2$ ionization-neutron calorimeter with a sum absorber thickness of $\sim$1000g/cm$^2$, typical spatial resolution of the order of 10cm, and dynamic range of ionization measurement channel about $\sim$10$^5$. Also, the use of saturation-free neutron detectors is anticipated for registration of the high- and low-energy hadron components in the region of shower core. A complex of underground detectors is designed for the study of muonic and penetrative nuclear-active components of the shower.
The full stack of data acquisition, detector calibration, and shower parameters restoration procedures are now completed, and the newly obtained shower size spectrum and lateral distribution of shower particles occur in agreement with conventional data. Future studies in the field of $10^{14}-10^{17}$eV cosmic ray physics to be held at the new shower installation are discussed. - [70] arXiv:1912.13400 [pdf, ps, other]
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Title: Binary stars: a cheat sheetAuthors: John SouthworthComments: 6 pages, 1 figure. Invited review for the BRITE Vienna conference, August 2019Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)
I present a brief summary of three different types of binary star - astrometric, spectroscopic and eclipsing - and tabulate the properties of these systems that can be determined directly from observations. Eclipsing binary stars are the most valuable of these, as they are our main source of direct mass and radius measurements for normal stars. In good cases, masses and radii can be obtained to better than 1% precision and accuracy using only photometry, spectroscopy and geometry. These measurements constitute vital empirical data against which theoretical models of stars can be verified and improved. I give examples of the use of these systems for constraining stellar theory and the distance scale, and conclude with a presentation of preliminary results for the solar-type eclipsing binary 1SWASP J034114.25+201253.5.
- [71] arXiv:1912.13517 [pdf, other]
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Title: Detection and Classification of Supernova Gravitational Waves Signals: A Deep Learning ApproachSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM)
We demonstrate the application of a convolutional neural network to the gravitational wave signals from core collapse supernovae. Using simulated time series of gravitational wave detectors, we show that based on the explosion mechanisms, a convolutional neural network can be used to detect and classify the gravitational wave signals buried in noise. For the waveforms used in the training of the convolutional neural network, our results suggest that a network of advanced LIGO, advanced VIRGO and KAGRA, or a network of LIGO A+, advanced VIRGO and KAGRA is likely to detect a magnetorotational core collapse supernovae within the Large and Small Magellanic Clouds, or a Galactic event if the explosion mechanism is the neutrino-driven mechanism. By testing the convolutional neural network with waveforms not used for training, we show that the true alarm probabilities are 52% and 83% at 60 kpc for waveforms R3E1AC and R4E1FC L. For waveforms s20 and SFHx at 10 kpc, the true alarm probabilities are 70% and 93% respectively. All at false alarm probability equal to 10%.
Cross-lists for Wed, 1 Jan 20
- [72] arXiv:1912.12390 (cross-list from hep-ph) [pdf, ps, other]
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Title: Comment on "Probing the Dark Matter-Electron Interactions via Hydrogen-Atmosphere Pulsating White Dwarfs''Comments: 2 pages, 1 figureSubjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
In Phys. Rev. D 98, 103023 (2018), a novel scenario was proposed to probe the interactions between dark matter (DM) particles and electrons, via hydrogen-atmosphere pulsating white dwarfs (DAVs) in globular clusters. The estimation showed that the scenario could hopefully test the parameter space: $5 \mathrm{GeV} \le m_{\chi} \le 10^{4} \mathrm{GeV}$ and $\sigma_{\chi,e} \ge 10^{-40} \mathrm{cm}^{2}$, where $m_{\chi}$ is the DM particle's mass and $\sigma_{\chi,e}$ is the elastic scattering cross section between DM and electron. In this comment, we have determined the exact lower limit of the testable DM particle mass $\sim 1.38 - 1.58 \mathrm{GeV}$, which depends on $\sigma_{\chi,e}$. This gives us a credible lower limit of the testable DM particle mass in above scenario, and provide a clear upper limit of the DM particle mass which we should consider in future research.
- [73] arXiv:1912.12469 (cross-list from gr-qc) [pdf, ps, other]
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Title: Weak Field Limit and Gravitational Waves in $f(T,B)$ Teleparallel GravityComments: 13 pagesSubjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)
We derive the gravitational waves for $f\left(T, B\right)$ gravity, an extension of teleparallel gravity containing the torsion scalar $T$ and the boundary term $B$, and demonstrate that it is equivalent to $f(R)$ gravity. Gravitational waves, in this theory, show three polarizations: the two standard, plus and cross, of General Relativity, which are purely transverse, massless tensor polarization modes with two-helicity, and an additional massive scalar mode with zero-helicity. The last one is a mix of a longitudinal mode and a transverse breathing mode. The boundary term $B$ excites the extra scalar polarization and the mass of scalar field breaks the symmetry of the TT gauge by adding a new degree of freedom, namely a single mixed scalar polarization.
- [74] arXiv:1912.12491 (cross-list from hep-ph) [pdf, ps, other]
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Title: New neutrino spin oscillations in moving matter and magnetic fieldsAuthors: Alexander StudenikinComments: 9 pages in LaTex, to appear in the Proceedings of the XXXIII Les Rencontres de Physique de la Vall\'ee d'Aoste - La Thuile 2019. arXiv admin note: text overlap with arXiv:1912.12494Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)
After a short introduction to the history of neutrino mixing and oscillations, we celebrate the 50th anniversary of the first analytical expression for the neutrino evolution probability obtained by Gribov and Pontecorvo in 1969 by the discussion of two new phenomena in neutrino oscillations: 1) the emergence of the neutrino spin and spin-flavour oscillations engendered by the transversal in respect to neutrino propagation matter currents, and 2) an inherent interplay of neutrino oscillations on the vacuum $\omega_{vac}=\frac{\Delta m^2}{4p}$ and magnetic $\omega_{B}=\mu B_{\perp}$ frequencies in the case of neutrino propagation in a constance magnetics field. We also predict a new phenomena of the modification of the flavour neutrino oscillations probability in moving matter that can be engendered by a non-vanishing matter transversal current ${\bf j}_{\perp}=n {\bf v}_{\perp}$.
- [75] arXiv:1912.12494 (cross-list from hep-ph) [pdf, ps, other]
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Title: Neutrino oscillations and evolution in external environments: New effectsAuthors: Alexander StudenikinComments: 6 pages in LaTex, to appear in the proceedings of the European Physical Society Conference on High Energy Physics - EPS-HEP2019 - 10-17 July, 2019, Ghent, Belgium. arXiv admin note: text overlap with arXiv:1912.12491Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)
During a period of about two decades we have realized a programme of systematic investigations of different aspects of neutrino propagation in extreme external environments and have predicted and studied several new phenomena that are engendered by the presence of external magnetic fields and dense matter. The starting point that underlies the research is the fact that the electromagnetic properties of neutrinos open a window to new physics \cite{Giunti:2014ixa,Studenikin:2008bd, Studenikin:2018vnp}. In these brief notes, we recall several new phenomena that have been proposed and investigated earlier. In particular, we discuss: 1) the spin light of neutrino in matter, 2) the neutrino energy quantization in rotating matter, and 3) neutrino start turning mechanism. Then we dwell on results of recent studies: 4) the effects of interplay of neutrino flavour and spin oscillations in a magnetic field, 5) the quantum theory of neutrino spin and spin-flavour oscillations engendered by the transversal mater currents, 6) the amplitude modulation of the flavour neutrino oscillation probability by the transversal matter current. As for references to the literature, only those papers are included in which a particular effect was proposed and considered for the first time and in a number of cases references are also be given to the most recent articles, which contain detailed references to the available literature on the issue.
- [76] arXiv:1912.12497 (cross-list from hep-ph) [pdf, ps, other]
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Title: Electromagnetic properties of neutrinosAuthors: Alexander StudenikinComments: 6 pages in LaTex, to appear in the proceedings of the European Physical Society Conference on High Energy Physics - EPS-HEP2019 - 10-17 July, 2019, Ghent, Belgium. arXiv admin note: substantial text overlap with arXiv:1801.08887, arXiv:1912.12501Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)
After a brief introduction to neutrino electromagnetic properties we focus on the most important constraints on neutrino magnetic moments, charge radii and millicharges from the terrestrial experiments and astrophysical considerations. The promising new possibilities for constraining neutrino electromagnetic properties in future experiments are also discussed.
- [77] arXiv:1912.12501 (cross-list from hep-ph) [pdf, ps, other]
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Title: Electromagnetic neutrinos: New constraints and new effects in oscillationsAuthors: Alexander StudenikinComments: 4 pages in LaTex, to appear in the proceedings of the 16th International Conference on Topics in Astroparticle and Underground Physics (TAUP 2019), 9-13 September 2019, Toyama, Japan. arXiv admin note: substantial text overlap with arXiv:1801.08887, arXiv:1912.12497Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)
A short overview of neutrino electromagnetic properties with focus on existed experimental constraints and future prospects is presented. The related new effect in neutrino flavour and spin-flavour oscillations in the transversal matter currents is introduced.
- [78] arXiv:1912.12503 (cross-list from physics.plasm-ph) [pdf, ps, other]
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Title: Generalized Magnetofluid Connections in Curved SpacetimeSubjects: Plasma Physics (physics.plasm-ph); High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
The ideal magnetohydrodynamic theorem on the conservation of the magnetic connections between plasma elements is extended to non-ideal relativistic plasmas in curved spacetime. The existence of generalized magnetofluid connections that are preserved by the plasma dynamics is formalized by means of a covariant connection equation that includes different non-ideal effects. These generalized connections are constituted by 2-dimensional hypersurfaces, which are linked to an antisymmetric tensor field that unifies the electromagnetic and fluid fields. They can be interpreted in terms of generalized magnetofluid vorticity field lines by considering a 3+1 foliation of spacetime and a time resetting projection that compensates for the loss of simultaneity in different reference frames between spatially separated events. The worldsheets of the generalized magnetofluid vorticity field lines play a fundamental role in the plasma dynamics by prohibiting evolutions that do not preserve the magnetofluid connectivity.
- [79] arXiv:1912.12670 (cross-list from gr-qc) [pdf, ps, other]
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Title: New application of the Killing vector field formalism: Modified periodic potential and two-level profiles of the axionic dark matter distributionComments: 12 pages, 5 figuresSubjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA); High Energy Physics - Theory (hep-th)
We consider the structure of halos of the axionic dark matter, which surround massive relativistic objects with static spherically symmetric gravitational field and monopole-type magneto-electric fields. We work with the model of pseudoscalar field with the extended periodic potential, which depends on additional arguments proportional to the moduli of the Killing vectors; in our approach they play the roles of model guiding functions. The covariant model of the axion field with this modified potential is equipped with the extended formalism of the Killing vector fields, which is established in analogy with the formalism of the Einstein-aether theory, based on the introduction of a unit timelike dynamic vector field. We study the equilibrium state of the axion field, for which the extended potential and its derivative vanish, and illustrate the established formalism by the analysis of two-level axionic dark matter profiles, for which the stage delimiters relate to the critical values of the modulus of the timelike Killing vector field.
- [80] arXiv:1912.12757 (cross-list from gr-qc) [pdf, other]
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Title: Single-field inflation in models with an $R^2$ termComments: 18 pages, 7 figures, invited talk given at Corfu Summer Institute 2019 "School and Workshops on Elementary Particle Physics and Gravity", 31 August - 25 September 2019, Corfu, GreeceSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)
We present two cases where the addition of the $R^2$ term to an inflationary model leads to single-field inflation instead of two-field inflation as is usually the case. In both cases we find that the effect of the $R^2$ term is to reduce the value of the tensor-to-scalar ratio $r$.
- [81] arXiv:1912.12805 (cross-list from gr-qc) [pdf, ps, other]
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Title: Second-order Gauge-invariant Cosmological Perturbation Theory: Current Status updated in 2019Authors: Kouji NakamuraComments: 40 pages, 2 figures, to be published as a book chapter in "Theory and Applications of Physical Science" from Book Publisher International; arXiv admin note: text overlap with arXiv:gr-qc/0605108, arXiv:1001.2621Subjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th); Mathematical Physics (math-ph)
The current status of the recent developments of the second-order gauge-invariant cosmological perturbation theory is reviewed. To show the essence of this perturbation theory, we concentrate only on the universe filled with a single scalar field. Through this review, we point out the problems which should be clarified for the further theoretical sophistication of this perturbation theory. This review is an extension of the review paper [K.~Nakamura, ``Second-Order Gauge-Invariant Cosmological Perturbation Theory: Current Status'', Advances in Astronomy, vol.2010 (2010), 576273.]. We also expect that this theoretical sophistication will be also useful to discuss the future developments in cosmology as a precise science.
- [82] arXiv:1912.12926 (cross-list from gr-qc) [pdf, ps, other]
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Title: Finite Action RevisitedAuthors: John D. BarrowComments: 14 pages, no figures or tablesSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
We evaluate the cosmological predictions that can be made assuming that the total action of the universe is finite. When initial and final singularities in curvature invariants are avoided, it leads to singularities in the gravitational action of the universe. A universe with finite action must have compact spatial sections giving a finite total lifetime. Compactification of flat and open universes is excluded. The universe cannot be dominated by massless scalar fields or the kinetic energy of self-interacting scalar fields or a p=\r{ho} perfect fluid on approach to the initial or final singularity The universe can contain perfect fluids with -1<p/\r{ho}<2 on approach to singularities. The universe cannot display a bounce' or indefinite cyclic behaviour to the past or the future. The ekpyrotic scenario with an effective fluid obeying p/\r{ho}>2 is excluded. Bouncing loop quantum gravity models are ruled out. The Einstein static and steady-state universes are excluded along with past or future eternal inflating universes. Anisotropies cannot dominate the dynamics on approach to singularities. Higher-order lagrangian theories of gravity are significantly constrained. Quadratic lagrangians with fluids satisfying p/\r{ho}>-1/3 are excluded. The Gauss-Bonnet term causes an action singularity despite not contributing terms to the field equations. Scalar-tensor theories like Brans-Dicke dominated by the scalar field on approach to singularities have action singularities. Dark energy cannot be a simple cosmological constant, as it would create an action singularity to the future. The dark energy must be an evolving energy density in a closed universe that produces collapse to a future singularity.
- [83] arXiv:1912.12934 (cross-list from physics.hist-ph) [pdf]
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Title: La orientación de las iglesias andinas de la región de Arica y Parinacota, Chile: una aproximación arqueoastronómicaComments: Article in Spanish, PDF document. Published version available at this http URL arXiv admin note: text overlap with arXiv:1803.08599Journal-ref: Arqueologia y Sociedad 32: 303-322, 2016Subjects: History and Philosophy of Physics (physics.hist-ph); Instrumentation and Methods for Astrophysics (astro-ph.IM)
The heritage Andean churches of Arica and Parinacota are representative of the majority of Christian churches in the region. Judging by their architecture, materiality and decoration, they have many features in common and are faithful to the intentions of their original builders. However, their geographical locations and the landscape that surrounds these churches show specific features for each of them. In particular, the orientation of the main axes (towards the altar of the churches) shows some diversity. In this extended area, with little attention from parish priests, the local Aymara culture, with its own worldview, surely engaged in a dialogue with the Western tradition in order to design and build the Indian Reductions. In this paper we present the results obtained from the analysis of the precise spatial orientations of all the cataloged churches, employing the tools of archaeoastronomy, as a complement to the architectural, historical and cultural research of the temples. We also comment briefly on some progress that we hope to make in neighboring areas to the region here studied, which include a large number of very old temples and are part, along with the churches here considered, of a common and widespread cultural koine.
- [84] arXiv:1912.12963 (cross-list from hep-ph) [pdf, ps, other]
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Title: The Minimal UV-induced Effective QCD Axion TheoryComments: 4 pagesSubjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
The characteristic axion couplings could be generated via effective couplings between the Standard Model (SM) fermions to a pseudo-Goldstone from a high-scale $U(1)$ Peccei-Quinn (PQ) symmetry breaking. Assuming that the UV-induced effective operators generate necessary couplings before the PQ symmetry breaking, and any low-scale couplings to the SM are restricted to the Yukawa sector, three minimal natural scenarios can be formulated, which provides a connection between the QCD-axions and mediators at the GUT/string scales. We find that the PQ symmetry breaking scale could be about $10^{15}$ GeV, higher than the classical QCD dark matter axion window but possible if the anthropic window is considered. We also propose an experiment to probe such scenarios. If the dark matter axion is discovered, they might suggest that we live in an atypical Hubble volume.
- [85] arXiv:1912.13128 (cross-list from gr-qc) [pdf, ps, other]
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Title: Unifying Inflation with Early and Late-time Dark Energy in $F(R)$ GravitySubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)
In this work we shall present models of $F(R)$ gravity which realize in a unified way the inflationary era along with a post-inflationary early dark energy era, with the late-time dark energy era. We shall use two approach methods in order to realize the unified cosmological eras, firstly we specify a Hubble rate which may describe the three distinct acceleration eras, and then by using well known $F(R)$ gravity reconstruction techniques, we shall find the differential equation which may yield the $F(R)$ gravity that realizes the cosmologies. In our second approach, we shall present in a qualitative way, several $F(R)$ gravities which unify the inflationary era with the early and late-time dark energy eras, and we discuss several qualitative issues related to the terms that realize the post-inflationary early dark energy era. We quantify our analysis by numerically solving the Friedmann equation, using the redshift as the main variable, and expressing all the physical quantities as functions of the statefinder $y_\mathrm{H}(z)$, which depends on the redshift and the Hubble rate $H(z)$. For the model studied numerically, we present the behavior of some statefinder quantities, like the deceleration parameter, and we calculate the dark energy density parameter and the dark energy equation of state parameter at present time. After demonstrating that the dark energy era is viable, we investigate when the early dark energy term does not affect the late-time era, and this restricts the free parameters of the model.
- [86] arXiv:1912.13197 (cross-list from physics.plasm-ph) [pdf, ps, other]
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Title: Nonlinear Coupling of Electromagnetic and Electron Acoustic Waves in Multi-Species Degenerate Astrophysical PlasmaComments: 8 pages of two-column text, accepted for publication to Physics of PlasmasSubjects: Plasma Physics (physics.plasm-ph); Solar and Stellar Astrophysics (astro-ph.SR)
Nonlinear wave--coupling is studied in a multi-species degenerate astrophysical plasma consisting of two electron species (at different temperatures): a highly degenerate main component plus a smaller classical relativistic flow immersed in a static neutralizing ion background. It is shown that the high frequency electromagnetic (HF EM) waves, through their strong nonlinear interactions with the electron--acoustic waves (sustained by a multi-electron component (degenerate) plasma surrounding a compact astrophysical object) can scatter to lower frequencies so that the radiation observed faraway will be spectrally shifted downwards. It is also shown that, under definite conditions, the EM waves could settle into stationary Solitonic states. It is expected that the effects of such structures may persist as detectable signatures in forms of modulated micro-pulses in the radiation observed far away from the accreting compact object. Both these effects will advance our abilities to interpret the radiation coming out of the compact objects.
- [87] arXiv:1912.13333 (cross-list from gr-qc) [pdf, other]
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Title: Horizonless ultracompact objects and dark matter in quadratic gravityComments: 26 pages, 2 figuresSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
We show that in quadratic gravity sufficiently light objects must be horizonless and construct explicit analytic examples of horizonless ultracompact objects (UCOs), which are more compact than Schwarzschild black holes. Due to the quadratic terms, gravity becomes soft and eventually vanishes in the high energy limit leading to a "linearization mechanism": light objects can be described by the linearized theory when their Schwarzschild radius is smaller than the Compton wavelength of the new gravitational degrees of freedom of quadratic gravity. As a result, we can analytically describe UCOs with a mass-to-radius ratio higher than for a Schwarzschild black hole. The corresponding spacetime is regular everywhere. We show that the Ostrogradsky instabilities can be avoided and discuss the relation with the Higgs vacuum metastability. Due to the lack of a horizon, light UCOs do not evaporate. Therefore, they may play the role of dark matter. We briefly discuss their phenomenology.
- [88] arXiv:1912.13488 (cross-list from hep-ph) [pdf, other]
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Title: Scalar Non-Standard Interactions of Neutrinos in Earth, Sun, Supernovae and Early UniverseComments: 34 pages, 7 figures, 2 TablesSubjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Experiment (hep-ex)
Non-standard interactions (NSI) of neutrinos with matter mediated by a scalar field would induce medium-dependent neutrino masses which can modify oscillation probabilities. Generating observable effects requires an ultra-light scalar mediator. We derive a general expression for the scalar NSI using techniques of quantum field theory at finite density and temperature and discuss various limiting cases applicable to the neutrino propagation in different media, such as the Earth, Sun, supernovae and early universe. We also analyze various terrestrial and space-based experimental constraints, as well as astrophysical and cosmological constraints on these NSI parameters, applicable to either Dirac or Majorana neutrinos. By combining all these constraints, we show that observable scalar NSI effects, although precluded in terrestrial experiments, are still possible in future solar and supernovae neutrino data, and in cosmological observations such as cosmic microwave background and big bang nucleosynthesis data.
Replacements for Wed, 1 Jan 20
- [89] arXiv:1506.05176 (replaced) [pdf, ps, other]
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Title: Infrared Two-Color Diagrams for AGB stars, post-AGB stars, and Planetary NebulaeAuthors: Kyung-Won SuhComments: 14 pages, 5 figures. Accepted for publication in ApJSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
- [90] arXiv:1509.01871 (replaced) [pdf, ps, other]
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Title: Dark Matter Admixed Type Ia SupernovaeComments: 11 pages, 14 figures, accepted by The Astrophysical Journal. Metadata updatedJournal-ref: Astrophysical Journal 812, 110 (2015)Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)
- [91] arXiv:1804.04265 (replaced) [pdf, other]
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Title: X-Ray Ionization of Planet-Opened Gaps in Protostellar DisksAuthors: Stacy Y. Kim (1, 2, 3), Neal J. Turner (4) ((1) California Institute of Technology, (2) Ohio State University, (3) University of Surrey, UK, (4) Jet Propulsion Laboratory, California Institute of Technology)Comments: 24 pages, 6 figures. Gap depths are now chosen to match recent hydrodynamical results. Accepted for publication in ApJSubjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
- [92] arXiv:1809.00259 (replaced) [pdf, ps, other]
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Title: Parameterized Post-Einsteinian Gravitational Waveforms in Various Modified Theories of GravityComments: 20 pages, 2 tables; v2: matches published version, updated abstract, updated references; v3: PPE parameters in dCS gravity correctedJournal-ref: Phys. Rev. D 98, 084042 (2018)Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE)
- [93] arXiv:1810.07032 (replaced) [pdf, other]
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Title: Fundamental ConceptsComments: 14 pages, 4 figures. To appear in "Tutorial Guide to X-ray and Gamma-ray Astronomy: Data Reduction and Analysis" (Ed. C. Bambi, Springer Singapore, 2020). v2: fixed some typos and updated some parts. arXiv admin note: text overlap with arXiv:1711.10256Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
- [94] arXiv:1810.07041 (replaced) [pdf, other]
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Title: Accreting Black HolesComments: 41 pages, 18 figures. To appear in "Tutorial Guide to X-ray and Gamma-ray Astronomy: Data Reduction and Analysis" (Ed. C. Bambi, Springer Singapore, 2020). v3: fixed some typos and updated some parts. arXiv admin note: substantial text overlap with arXiv:1711.10256Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
- [95] arXiv:1901.10007 (replaced) [pdf, ps, other]
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Title: Explosive Nucleosynthesis in Sub-Chandrasekhar Mass White Dwarf Models for Type Ia Supernovae: Dependence on Model ParametersComments: 56 pages, 89 figures, submitted to Astrophysical Journal at 15 January 2019, accepted at 25 November 2019. Some color plots in Appendix B removed to lower the file size. Text, figures and references updated to match with accepted versionSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [96] arXiv:1901.11136 (replaced) [pdf, ps, other]
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Title: Pulsational Pair-instability Supernovae. I. Pre-collapse Evolution and Pulsational Mass EjectionComments: 33 pages, 57 figures, submitted at 29 January 2019, revised at 16 October 2019, accepted at 20 October 2019; published 11 December 2019. References and metadata updatedJournal-ref: Astrophysical Journal 887, 72 (2019)Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
- [97] arXiv:1904.02720 (replaced) [pdf]
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Title: Bottom-up Acceleration of Ultra-High-Energy Cosmic Rays in the Jets of Active Galactic NucleiComments: 15 pages, 11 figuresJournal-ref: ApJ 886 8 (2019)Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
- [98] arXiv:1905.01256 (replaced) [pdf, ps, other]
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Title: Generalized quenching of large-scale magnetic dynamos in anisotropic flowsComments: 9 pages, 2 figures; submitted to Physical Review ResearchSubjects: Fluid Dynamics (physics.flu-dyn); Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR); Plasma Physics (physics.plasm-ph)
- [99] arXiv:1906.11189 (replaced) [pdf, other]
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Title: Radial oscillations of quark stars from perturbative QCDComments: 10 pages, 5 figures; v2: figures added, references added, modifications to the textJournal-ref: Phys. Rev. D 100, 114041 (2019)Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
- [100] arXiv:1907.01981 (replaced) [pdf, other]
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Title: The Karl G. Jansky Very Large Array Sky Survey (VLASS). Science case and survey designAuthors: M. Lacy (1), S.A. Baum (2), C.J. Chandler (1), S. Chatterjee (3), T.E. Clarke (4), S. Deustua (5), J. English (2), J. Farnes (6), B.M. Gaensler (7), N. Gugliucci (8), G. Hallinan (9), B.R. Kent (1), A. Kimball (1), C.J. Law (9,10), T.J.W. Lazio (11), J. Marvil (1), S.A. Mao (12), D. Medlin (1), K. Mooley (9), E.J. Murphy (1), S. Myers (1), R. Osten (5), G.T. Richards (13), E. Rosolowsky (14), L. Rudnick (15), F. Schinzel (1), G.R. Sivakoff (14), L.O. Sjouwerman (1), R. Taylor (16, 17), R.L. White (5), J. Wrobel (1), H. Andernach (18), A.J. Beasley (1), E. Berger (19), S. Bhatnagar (1), M. Birkinshaw (20), G.C. Bower (21), W.N. Brandt (22, 23, 24), S. Brown (25), S. Burke-Spolaor (26, 27), B.J. Butler (1), J. Comerford (28), P.B. Demorest (1), H. Fu (25), S. Giacintucci (4), K. Golap (1), et al. (32 additional authors not shown)Comments: 34 pages, accepted by PASP (modified from prior version to address referee's and coauthor comments). (v2) Minor fixes to author listSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Astrophysics of Galaxies (astro-ph.GA); High Energy Astrophysical Phenomena (astro-ph.HE)
- [101] arXiv:1907.06272 (replaced) [pdf, ps, other]
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Title: Extending light WIMP searches to single scintillation photons in LUXAuthors: D. S. Akerib, S. Alsum, H. M. Araújo, X. Bai, A. J. Bailey, J. Balajthy, A. Baxter, P. Beltrame, E. P. Bernard, A. Bernstein, T. P. Biesiadzinski, E. M. Boulton, B. Boxer, P. Brás, S. Burdin, D. Byram, S. B. Cahn, M. C. Carmona-Benitez, C. Chan, A. A. Chiller, C. Chiller, A. Currie, J. E. Cutter, L. de Viveiros, A. Dobi, J. E. Y. Dobson, E. Druszkiewicz, B. N. Edwards, C. H. Faham, S. R. Fallon, A. Fan, S. Fiorucci, R. J. Gaitskell, V. M. Gehman, J. Genovesi, C. Ghag, K. R. Gibson, M. G. D. Gilchriese, E. Grace, C. Gwilliam, C. R. Hall, M. Hanhardt, S. J. Haselschwardt, S. A. Hertel, D. P. Hogan, M. Horn, D. Q. Huang, C. M. Ignarra, R. G. Jacobsen, O. Jahangir, W. Ji, K. Kamdin, K. Kazka, D. Khaitan, R. Knoche, E. V. Korolkova, S. Kravitz, V. A. Kudryavtsev, N. A. Larsen, E. Leason, et al. (65 additional authors not shown)Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Physics - Experiment (hep-ex); Instrumentation and Detectors (physics.ins-det)
- [102] arXiv:1907.06928 (replaced) [pdf, other]
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Title: Generic energy transport solutions to the solar abundance problem -- a hint of new physicsAuthors: Anton V. SokolovComments: Physical model simplified and clarified; 32 pages, 10 figures; submitted to JCAPSubjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Physics - Phenomenology (hep-ph)
- [103] arXiv:1907.10059 (replaced) [pdf, other]
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Title: Testing Gravity with Gravitational Waves from Binary Black Hole Mergers: Contributions from Amplitude CorrectionsComments: v2: The third author has been added, which was accidentally missed in the first submission; v3: matches the published versionJournal-ref: Phys. Rev. D 100, 104001 (2019)Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE)
- [104] arXiv:1908.01158 (replaced) [pdf, other]
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Title: Finding Singularities in Gravitational LensingComments: 13 pages. six figures. Accepted for publication in the MNRASSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
- [105] arXiv:1908.01773 (replaced) [pdf, other]
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Title: Gravitational Lensing Signatures of Axion Dark Matter Minihalos in Highly Magnified StarsComments: Accepted for publication in the Astronomical Journal; Figure 6 updated with time axis corrected; no major changes in conclusion and textSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)
- [106] arXiv:1908.02668 (replaced) [pdf, other]
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Title: Fractional Dark Matter decay: cosmological imprints and observational constraintsComments: 34 pages, 18 figures, 5 tables, accepted for publication in JCAPSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)
- [107] arXiv:1908.02928 (replaced) [pdf, other]
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Title: Influence of density dependence of symmetry energy in hot and dense matter for supernova simulationsComments: 21 pages, 18 figures, revised version accepted for publication in ApJJournal-ref: Astrophys. J. 887 (2019) 110Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
- [108] arXiv:1908.05102 (replaced) [pdf, ps, other]
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Title: Accretion-Induced Collapse of Dark Matter Admixed White Dwarfs -- I: Formation of Low-mass Neutron StarsComments: 14 pages, 12 figures. Submitted to Astrophysical Journal at 9 July 2019, accepted at 13 August 2019, published at 7 October 2019. References and metadata updatedJournal-ref: Astrophysical Journal 884, 9 (2019)Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
- [109] arXiv:1908.08217 (replaced) [pdf, other]
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Title: Nonlinear Reconstruction of the Velocity FieldComments: 14 pages, 12 figures, matched to the published versionJournal-ref: The Astrophysical Journal, Volume 887, Number 2, Page 265 (2019)Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [110] arXiv:1908.09722 (replaced) [pdf, other]
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Title: Neutron Star Matter as a Relativistic Fermi LiquidComments: 36 pages, 12 figures, published in PRCJournal-ref: Phys. Rev. C 100, 065807 (2019)Subjects: Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
- [111] arXiv:1908.10376 (replaced) [pdf, other]
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Title: On the orientation of the crescent image of M87*Comments: 7 pages, 7 figures, accepted in A&A Main JournalSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)
- [112] arXiv:1908.10549 (replaced) [pdf, other]
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Title: Program objectives and specifications for the Ultra-Fast Astronomy observatoryAuthors: Siyang Li (a), George F. Smoot (a-h), Bruce Grossan (b, d), Albert Wai Kit Lau (e), Marzhan Bekbalanova (d), Mehdi Shafiee (d), Thorsten Stezelberger (c) ((a) Department of Physics, University of California, Berkeley, USA, (b) Space Sciences Laboratory, University of California, Berkeley, USA, (c) Lawrence Berkeley National Laboratory, USA, (d) Energetic Cosmos Laboratory, Nazarbayev University, Kazakhstan, (e) Department of Physics, Hong Kong University of Science and Technology, China, (f) Institute for Advanced Study, Hong Kong University of Science and Technology, China, (g) Department of Physics, Université Paris Diderot, France, (h) Paris Centre for Cosmological Physics, Université Paris, France)Comments: 9 pages, 7 figures, 1 tableJournal-ref: Proc. SPIE 11341, Space Optics, Telescopes, and Instrumentation (2019)Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)
- [113] arXiv:1909.02223 (replaced) [pdf, other]
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Title: Deciphering Residual Emissions: Time-Dependent Models for the Non-Thermal Interstellar Radiation from the Milky WayComments: Accepted version. Published online Dec 26: ApJ 887, 250 (2019). 22 pages, 14 figures, 2 movies. Movies and configuration files available at the GALPROP website: this https URLSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [114] arXiv:1909.07396 (replaced) [pdf, ps, other]
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Title: The Lyman Continuum Escape Survey -- II: Ionizing Radiation as a Function of the [OIII]/[OII] Line RatioComments: 15 pages, 6 figures. Accepted for publication in ApJSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [115] arXiv:1909.11665 (replaced) [pdf, other]
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Title: The Large-Misalignment Mechanism for the Formation of Compact Axion Structures: Signatures from the QCD Axion to Fuzzy Dark MatterAuthors: Asimina Arvanitaki, Savas Dimopoulos, Marios Galanis, Luis Lehner, Jedidiah O. Thompson, Ken Van TilburgComments: 45 pages, 28 figuresSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
- [116] arXiv:1910.03457 (replaced) [pdf, ps, other]
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Title: Hills and holes in the microlensing light curve due to plasma environment around gravitational lensComments: Published in MNRASJournal-ref: MNRAS 491, 5636-5649 (2020)Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA)
- [117] arXiv:1910.08608 (replaced) [pdf, other]
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Title: Detecting Gravitational Scattering of Interstellar Objects Using Pulsar TimingComments: 12 pages, 6 figures. Accepted for publication in ApJSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [118] arXiv:1910.09523 (replaced) [pdf, other]
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Title: Temporal Variability in Hot Jupiter AtmospheresComments: 18 pages, 12 figures, updated to reflect published versionJournal-ref: The Astrophysical Journal, 888:2, 2020 January 1Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Atmospheric and Oceanic Physics (physics.ao-ph)
- [119] arXiv:1910.12559 (replaced) [pdf, other]
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Title: AttoSats: ChipSats, other Gram-Scale Spacecraft, and BeyondSubjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Space Physics (physics.space-ph)
- [120] arXiv:1910.13409 (replaced) [pdf, other]
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Title: GROWTH on S190814bv: Deep Synoptic Limits on the Optical/Near-Infrared Counterpart to a Neutron Star-Black Hole MergerAuthors: Igor Andreoni, Daniel A. Goldstein, Mansi M. Kasliwal, Peter E. Nugent, Rongpu Zhou, Jeffrey A. Newman, Mattia Bulla, Francois Foucart, Kenta Hotokezaka, Ehud Nakar, Samaya Nissanke, Geert Raaijmakers, Joshua S. Bloom, Kishalay De, Jacob E. Jencson, Charlotte Ward, Tomás Ahumada, Shreya Anand, David A. H. Buckley, Maria D. Caballero-García, Alberto J. Castro-Tirado, Christopher M. Copperwheat, Michael W. Coughlin, S. Bradley Cenko, Mariusz Gromadzki, Youdong D. Hu, Viraj R. Karambelkar, Daniel A. Perley, Yashvi Sharma, Azamat F. Valeev, David O. Cook, U. Christoffer Fremling, Harsh Kumar, Kirsty Taggart, Ashot Bagdasaryan, Jeff Cooke, Aishwarya Dahiwale, Suhail Dhawan, Dougal Dobie, Pradip Gatkine, V. Zach Golkhou, Ariel Goobar, Andreas Guerra Chaves, Matthew Hankins, David L. Kaplan, et al. (7 additional authors not shown)Comments: Accepted to ApJ with no major changesSubjects: High Energy Astrophysical Phenomena (astro-ph.HE)
- [121] arXiv:1910.13779 (replaced) [pdf, ps, other]
- [122] arXiv:1910.14414 (replaced) [pdf, ps, other]
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Title: Preferred-frame Effects, the $H_0$ Tension, and Probes of Hořava-Lifshitz GravityAuthors: Nils A. NilssonComments: Clarified methodology, restricted attention to one model. 10 pages, no figuresSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [123] arXiv:1911.00777 (replaced) [pdf, ps, other]
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Title: SDSS-IV MaNGA: Internal mass distributions and orbital structures of early-type galaxies and their dependence on environmentComments: 19 pages, 18 figuresSubjects: Astrophysics of Galaxies (astro-ph.GA)
- [124] arXiv:1911.11766 (replaced) [pdf, other]
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Title: Measuring lensing ratios with future cosmological surveysComments: 15 pages, 12 figures, 1 table, submitted to PRDSubjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [125] arXiv:1912.01518 (replaced) [pdf, ps, other]
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Title: Effects of the general relativistic spin precessions on the habitability of rogue planets orbiting supermassive black holesAuthors: Lorenzo IorioComments: LaTex2e, 15 pages, 2 figures, no tables. Some minor changes, and a mistake correctedSubjects: Earth and Planetary Astrophysics (astro-ph.EP); General Relativity and Quantum Cosmology (gr-qc); Popular Physics (physics.pop-ph); Space Physics (physics.space-ph)
- [126] arXiv:1912.02730 (replaced) [pdf, ps, other]
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Title: Strong Soft X-ray Excess in 2015 XMM-Newton Observation of BL--Lac OJ~287Comments: 12 pages, 5 figures, 2 tables; accepted for publication in the ApJ journalSubjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
- [127] arXiv:1912.05884 (replaced) [pdf, other]
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Title: Hot Super-Earths with Hydrogen Atmospheres: A Model Explaining Their Paradoxical ExistenceComments: 20 pages, 15 figuresSubjects: Earth and Planetary Astrophysics (astro-ph.EP)
- [128] arXiv:1912.07049 (replaced) [pdf, ps, other]
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Title: Superpotential method for $F(R)$ cosmological modelsComments: 10 pages, references addedSubjects: General Relativity and Quantum Cosmology (gr-qc); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
- [129] arXiv:1912.07826 (replaced) [pdf, other]
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Title: Nature and Origins of Rich Complexes of C IV Associated Absorption LinesComments: 23 pages, 8 figures, 7 tables. arXiv admin note: text overlap with arXiv:1809.05433Journal-ref: The Astrophysical Journal, 887:78 (23pp), 2019 December 10Subjects: Astrophysics of Galaxies (astro-ph.GA)
- [130] arXiv:1912.08069 (replaced) [pdf]
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Title: Preliminary analysis of periodogram shapes and their classificationAuthors: L.S. KudashkinaComments: 6 figures, 2 tablesSubjects: Solar and Stellar Astrophysics (astro-ph.SR)
- [131] arXiv:1912.09886 (replaced) [pdf, other]
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Title: The multi-thermal chromosphere: inversions of ALMA and IRIS dataAuthors: J. M. da Silva Santos, J. de la Cruz Rodríguez, J. Leenaarts, G. Chintzoglou, B. De Pontieu, S. Wedemeyer, M. SzydlarskiComments: 17 pages, 12 figures; accepted in A&A (added references, corrected typos)Subjects: Solar and Stellar Astrophysics (astro-ph.SR)
- [132] arXiv:1912.10582 (replaced) [pdf, other]
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Title: Quantum corrected black holes: quasinormal modes, scattering, shadowsAuthors: R. A. KonoplyaComments: 6 pages, 3 figures, revtex, some numerical data is corrected, new material is addedSubjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)
- [133] arXiv:1912.10649 (replaced) [pdf, other]
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Title: Gaia-assisted discovery of a detached low-ionisation BAL quasar with very large ejection velocitiesAuthors: J. P. U. Fynbo, P. Møller, K. E. Heintz, J. N. Burchett, L. Christensen, S. J. Geier, P. Jakobsson, J.-K. Krogager, C. Ledoux, B. Milvang-Jensen, P. Noterdaeme, J. X. Prochaska, T. M. TrippComments: 6 pages, 5 figures. Accepted for publication in A&ASubjects: Astrophysics of Galaxies (astro-ph.GA)
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