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New submissions for Wed, 20 Nov 19

[1]  arXiv:1911.07851 [pdf, other]

Title: Chemical enrichment and host galaxies of extremely-strong intervening DLAs towards quasars

Authors: A. Ranjan, P. Noterdaeme, J.-K. Krogager, P. Petitjean, R. Srianand, S. A. Balashev, N. Gupta, C. Ledoux

Comments: 13 page paper with 8 additional appendix pages, 10 main figures with 23 figures in appendix

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We present the results from VLT/X-shooter spectroscopic observations of 11 extremely strong intervening damped Lyman-alpha absorbers (ESDLAs) initially selected as high N(Hi) (i.e.>=5x10^21 cm-2) candidates from the Sloan Digital Sky Survey (SDSS). We confirm the high Hi column densities which we measure to be in the range log N(Hi) = 21.6-22.4. Molecular hydrogen is detected with high column densities (N(H_2)>=10^18 cm-2) in five out of eleven systems, three of which are reported here for the first time. We compare the chemical properties of this sample of ESDLAs, supplemented with literature measurements, to that of DLAs located at the redshift of long-duration gamma-ray bursts (GRB-DLAs). We confirm that the two populations are almost indistinguishable in terms of chemical enrichment, H_2 column density and gas kinematics. All this suggests that ESDLAs and GRB-DLAs probe similar galactic environments. We search for the galaxy counterparts of ESDLAs and find associated emission lines in three out of eleven systems, two of which are reported here for the first time (towards the quasars SDSS J002503.03+114547.80 and SDSS J114347.21+142021.60, respectively). The measured separations between the quasar sightlines and the emission associated with the ESDLA galaxy are all very small (rho < 3 kpc). While the small impact parameters are similar to what is observed for GRB-DLAs, the associated star-formation rates are on average lower than seen for GRB host galaxies. This is explained by long-duration GRBs being associated with the death of massive stars, hence pinpointing regions of active star formation in the GRB host galaxies. Our observations support the suggestion from the literature that ESDLAs could act as blind analogues of GRB-DLAs, probing high column density neutral gas in the heart of high-redshift galaxies, without any prior on the instantaneous star-formation rate.

[2]  arXiv:1911.07853 [pdf, other]

Title: Imprints of the Early Universe on Axion Dark Matter Substructure

Authors: Nikita Blinov, Matthew J. Dolan, Patrick Draper

Comments: 33 pages, 12 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

Despite considerable experimental progress large parts of the axion-like particle (ALP) parameter space remain difficult to probe in terrestrial experiments. In some cases, however, small-scale structure of the ALP dark matter (DM) distribution is strongly enhanced, offering opportunities for astrophysical tests. Such an enhancement can be produced by a period of pre-nucleosynthesis early matter domination (EMD). This cosmology arises in many ultraviolet completions and generates the correct relic abundance for weak coupling $f_a\sim 10^{16}$ GeV, ALP masses in the range $10^{-13}$ eV $<m_a < 1$ eV, and without fine-tuning of the initial misalignment angle. This range includes the QCD axion around $10^{-9}-10^{-8}$ eV. EMD enhances the growth of ALP small-scale structure, leading to the formation of dense ALP miniclusters. We study the interplay between the initial ALP oscillation, reheating temperature, and effective pressure to provide analytic estimates of the minicluster abundance and properties. ALP miniclusters in the EMD cosmology are denser and more abundant than in $\Lambda$CDM. While enhanced substructure generically reduces the prospects of direct detection experiments, we show that pulsar timing and lensing observations can discover these minihalos over a large range of ALP masses and reheating temperatures.

[3]  arXiv:1911.07854 [pdf, other]

Title: The Star-Forming Interstellar Medium of Lyman Break Galaxy Analogs

Authors: John F. Wu, Andrew J. Baker, Timothy M. Heckman, Erin K. S. Hicks, Dieter Lutz, Linda J. Tacconi

Comments: Accepted for publication in ApJ; 30 pages, 9 figures

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We present VLT/SINFONI near-infrared (NIR) integral field spectroscopy of six $z \sim 0.2$ Lyman break galaxy "analogs" (LBAs), from which we detect HI, HeI, and [FeII] recombination lines, and multiple H$_2$ ro-vibrational lines in emission. Pa$\alpha$ kinematics reveal high velocity dispersions and low rotational velocities relative to random motions ($\langle v/\sigma \rangle = 1.2 \pm 0.8$). Matched-aperture comparisons of H$\beta$, H$\alpha$, and Pa$\alpha$ reveal that the nebular color excesses are lower relative to the continuum color excesses than is the case for typical local star-forming systems. We compare observed HeI/HI recombination line ratios to photoionization models to gauge the effective temperatures (T$_{\rm eff}$) of massive ionizing stars, finding the properties of at least one LBA are consistent with extra heating from an active galactic nucleus (AGN) and/or an overabundance of massive stars. We use H$_2$ 1-0 S($\cdot$) ro-vibrational spectra to determine rotational excitation temperature $T_{\rm ex} \sim 2000$ K for warm molecular gas, which we attribute to UV heating in dense photon-dominated regions. Spatially resolved NIR line ratios favor excitation by massive, young stars, rather than supernovae or AGN feedback. Our results suggest that the local analogs of Lyman break galaxies are primarily subject to strong feedback from recent star formation, with evidence for AGN and outflows in some cases.

[4]  arXiv:1911.07855 [pdf, ps, other]

Title: The impact of our local environment on cosmological statistics

Authors: Alex Hall

Comments: 20 pages, 9 figures. Submitted to Physical Review D

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We conduct a thorough investigation into the possibility that residing in an overdense region of the Universe may induce bias in measurements of the large-scale structure. We compute the conditional correlation function and angular power spectrum of density and lensing fluctuations while holding the local spherically-averaged density fixed and show that for Gaussian fields this has no effect on the angular power at $l>0$. We identify a range of scales where a perturbative approach allows analytic progress to be made, and we compute leading-order conditional power spectra using an Edgeworth expansion and second-order perturbation theory. We find no evidence for any significant bias to cosmological power spectra from our local density contrast. We show that when smoothed over a large region around the observer, conditioning on the local density typically affects density power spectra by less than a percent at cosmological distances, below cosmic variance. We find that while typical corrections to the lensing angular power spectrum can be at the 10% level on the largest angular scales and for source redshifts $z_s \lesssim 0.1$, for the typical redshifts targeted by upcoming wide imaging surveys the corrections are sub-percent and negligible, in contrast to previous claims in the literature. Using an estimate of the local spherically-averaged density from a composite galaxy redshift catalogue we find that the corrections from conditioning on our own local density are below cosmic variance and subdominant to other non-linear effects. We discuss the potential implications of our results for cosmology and point out that a measurement of the local density contrast may be used as a consistency test of cosmological models.

[5]  arXiv:1911.07858 [pdf, other]

Title: Unveiling Sizes of Compact AGN Hosts with ALMA

Authors: Yu-Yen Chang, Emeric Le Floc'h, Stéphanie Juneau, Elisabete da Cunha, Mara Salvato, Avishai Dekel, Francesca Civano, Stefano Marchesi, Hyewon Suh, Wei-Hao Wang

Comments: accepted for publication in ApJ

Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We present rest-frame far-infrared (FIR) and optical size measurements of AGN hosts and star-forming galaxies in the COSMOS field, enabled by high-resolution ALMA/1 mm (0.1 arcsec - 0.4 arcsec) and HST/F814W imaging (~ 0.1 arcsec). Our sample includes 27 galaxies at z<2.5, classified as infrared-selected AGN (3 sources), X-ray selected AGN (4 sources), and non-AGN star-forming galaxies (20 sources), for which high-resolution Band 6/7 ALMA images are available at 1 mm from our own observing program as well as archival observations. The sizes and SFR surface densities measured from both ALMA/1 mm and HST/F814W images show that obscured AGN host galaxies are more compact than non-AGN star-forming galaxies at similar redshift and stellar mass. This result suggests that the obscured accretion phase may be related to galaxies experiencing a compaction of their gaseous component, which could be associated with enhanced central star formation before a subsequent quenching driving the formation of compact passive galaxies. Moreover, most of the detected and stacked rest-frame FIR sizes of AGNs in our sample are similar or more compact than their rest-frame optical sizes, which is consistent with recent results of ALMA detected sources. This might be explained by the fact that the dusty starbursts take place in the compact regions, and suggests that the star formation mechanisms in the compact regions of AGN hosts are similar to those observed in star-forming galaxies observed with ALMA.

[6]  arXiv:1911.07863 [pdf, other]

Title: The Formation and Evolution of Wide-Orbit Stellar Multiples In Magnetized Clouds

Authors: Aaron T. Lee, Stella S. R. Offner, Kaitlin M. Kratter, Rachel A. Smullen, Pak Shing Li

Comments: Accepted to ApJ. 28 pages, 23 figures, comments from the community welcomed

Subjects: Astrophysics of Galaxies (astro-ph.GA)

Stars rarely form in isolation. Nearly half of the stars in the Milky Way have a companion, and this fraction increases in star-forming regions. However, why some dense cores and filaments form bound pairs while others form single stars remains unclear. We present a set of three-dimensional, gravo-magnetohydrodynamic simulations of turbulent star-forming clouds, aimed at understanding the formation and evolution of multiple-star systems formed through large scale (>~$10^3$ AU) turbulent fragmentation. We investigate three global magnetic field strengths, with global mass-to-flux ratios of $\mu_\phi$=2, 8, and 32. The initial separations of protostars in multiples depends on the global magnetic field strength, with stronger magnetic fields (e.g., $\mu_\phi$=2) suppressing fragmentation on smaller scales. The overall multiplicity fraction (MF) is between 0.4-0.6 for our strong and intermediate magnetic field strengths, which is in agreement with observations. The weak field case has a lower fraction. The MF is relatively constant throughout the simulations, even though stellar densities increase as collapse continues. While the MF rarely exceeds 60% in all three simulations, over 80% of all protostars are part of a binary system at some point. We additionally find that the distribution of binary spin mis-alignment angles is consistent with a randomized distribution. In all three simulations, several binaries originate with wide separations and dynamically evolve to <~ $10^2$ AU separations. We show that a simple model of mass accretion and dynamical friction with the gas can explain this orbital evolution.

[7]  arXiv:1911.07864 [pdf, other]

Title: A Catalog of AGN Host Galaxies Observed with HST/ACS: Correlations between Star Formation and AGN Activity

Authors: Aaron Stemo, Julia M. Comerford, R. Scott Barrows, Daniel Stern, Roberto J. Assef, Roger L. Griffith

Comments: 20 pages, 8 figures, accepted for publication in ApJ

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We present the Advanced Camera for Surveys Active Galactic Nuclei (ACS-AGN) Catalog, a catalog of 2585 active galactic nucleus (AGN) host galaxies that are at redshifts 0.2<z<2.5 and that were imaged with the Hubble Space Telescope's Advanced Camera for Surveys (ACS). Using the ACS General Catalog (ACS-GC) as our initial sample, we select an AGN subsample using Spitzer and Chandra data along with their respective established AGN selection criteria. We then gather further multi-wavelength photometric data in order to construct spectral energy distributions (SEDs). Using these SEDs we are able to derive multiple AGN and host galaxy properties, such as star formation rate, AGN luminosity, stellar mass, and nuclear column density. From these data, we show that AGN host galaxies tend to lie below the star-forming main sequence, with X-ray-selected AGN host galaxies being more offset than IR-selected AGN host galaxies. This suggests that there is some process, possibly negative feedback, in AGN host galaxies causing decreased star formation. We also demonstrate that there is a positive trend between star formation rate and AGN luminosity in AGN host galaxies, in individual redshift bins and across all redshift bins, and that both are correlated with the stellar mass of their galaxies. This points towards an underlying link between the stellar mass, stellar growth, and SMBH growth in a galaxy.

[8]  arXiv:1911.07865 [pdf, other]

Title: Search for dark matter induced de-excitation of $^{180}$Ta$\rm ^m$

Authors: Björn Lehnert, Harikrishnan Ramani, Mikael Hult, Guillaume Lutter, Maxim Pospelov, Surjeet Rajendran, Kai Zuber

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Instrumentation and Detectors (physics.ins-det)

Weak-scale dark matter particles, in collisions with nuclei, can mediate transitions between different nuclear energy levels. In particular, owing to sizeable momentum exchange, dark matter particles can enable de-excitation of nuclear isomers that are extremely long lived with respect to regular radioactive decays. In this paper, we utilize data from a past experiment with $^{180}$Ta$\rm ^m$ to search for $\gamma$-lines that would accompany dark matter induced de-excitation of this isomer. Non-observation of such transitions above background yields the first direct constraint on the lifetime of $^{180}$Ta$\rm ^m$ against DM-initiated transitions: $T_{1/2}>1.3\times 10^{14}$~a at 90\% C.I. Using this result, we derive novel constraints on dark matter models with strongly interacting relics, and on models with inelastic dark matter particles. Existing constraints are strengthened by this independent new method. The obtained limits are also valid for the Standard Model $\gamma$-decay of $^{180}$Ta$\rm ^m$.

[9]  arXiv:1911.07869 [pdf, ps, other]

Title: Maximum Cosmological Information from Type-Ia Supernova Observations

Authors: Jaiyul Yoo (Zürich)

Comments: 6 pages, 3 figures, comments welcome

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

Type-Ia supernova observations yield estimates of the luminosity distance, which includes not only the background luminosity distance, but also the fluctuation due to inhomogeneities in the Universe. In particular, the spatial correlation of the host galaxies is a dominant source of the fluctuation in the luminosity distance measurements. Utilizing the recent theoretical framework that accurately quantifies the information contents accounting for the three-dimensional correlation of the observables on the past-light cone, we compute the maximum cosmological information obtainable from idealized supernova surveys as a function of maximum redshift $z_m$. Here we consider two cosmological parameters $\Omega_m$ and $w_0$ and show that these parameters can be constrained at maximum 1% levels in an idealized survey with $z_m=1$. We discuss how these fundamental limits set by cosmic variance can be overcome.

[10]  arXiv:1911.07870 [pdf, other]

Title: Radio halos of star forming galaxies

Authors: Aditi Vijayan, Biman B. Nath, Prateek Sharma, Yuri Shchekinov

Comments: 12 pages, 12 figures, Under Review with MNRAS

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We study the synchrotron radio emission from extra-planar regions of star forming galaxies. We use ideal magneto-hydrodynamical (MHD) simulations of a rotating Milky Way-type disk galaxy with distributed star formation sites for three star formation rates (SFRs) (0.3, 3, 30 M$_{\odot}$ yr$^{-1}$). From our simulations, we see emergence of galactic-scale magnetised outflows, carrying gas from the disk. We compare the morphology of the outflowing gas with hydrodynamic (HD) simulations. We look at the spatial distribution of magnetic field in the outflows. Assuming that a certain fraction of gas energy density is converted into cosmic ray energy density, and using information about the magnetic field, we obtain synchrotron emissivity throughout the simulation domain. We generate the surface brightness maps at a frequency of 1.4 GHz. The outflows are more extended in the vertical direction than radial and hence have an oblate shape. We further find that the matter right behind the outer shock, shines brighter in these maps than that above or below. To understand whether this feature can be observed, we produce vertical intensity profiles. We convolve the vertical intensity profile with the typical beam sizes of radio telescopes, for a galaxy located at 10 Mpc (similar to NGC 891) in order to estimate the radio scale height to compare with observations. We find that for our SFRs this feature will lie below the RMS noise limit of instruments. The radio scale height is found to be $\sim 300-1200$ pc , depending on the resolution of the telescope. We relate the advection speed of the outer shock with the surface density of star formation as $\rm{v}_{\rm adv} \propto \Sigma_{\rm SFR}^{0.3}$ which is consistent with earlier observations and analytical estimates.

[11]  arXiv:1911.07872 [pdf, other]

Title: Kinematics and Dynamics of Multiphase Outflows in Simulations of the Star-Forming Galactic ISM

Authors: Aditi Vijayan, Chang-Goo Kim, Lucia Armillotta, Eve C. Ostriker, Miao Li

Comments: 22 pages, Submitted to ApJ

Subjects: Astrophysics of Galaxies (astro-ph.GA)

Galactic outflows produced by stellar feedback are known to be multiphase in nature. Both observations and simulations indicate that the material within several kpc of galactic disk mid-planes consists of warm clouds embedded within a hot wind. A theoretical understanding of the outflow phenomenon, including both winds and fountain flows, requires study of the interactions among thermal phases. We develop a method to quantify these interactions via measurements of mass, momentum, and energy flux exchanges using temporally and spatially averaged quantities and conservation laws. We apply this method to a star-forming ISM MHD simulation based on the TIGRESS framework, for Solar neighbourhood conditions. To evaluate the extent of interactions among the phases, we first examine the validity of the ``ballistic model,'' which predicts trajectories of the warm phase ($5050\,\rm{K}<T<2\times10^4\,\rm{K}$) treated as non-interacting clouds. This model is successful at intermediate vertical velocities ($ 50$ km s$^{-1}$ $\lesssim |v_z| \lesssim 100 $ km s$^{-1}$), but at higher velocities we observe an excess in simulated warm outflow compared to the ballistic model. This discrepancy cannot be fully accounted for by cooling of high-velocity intermediate-temperature ($2\times10^4\,\rm{K}<T<5\times10^5\,\rm{K}$) gas. By examining the fluxes of mass, momentum and energy, we conclude that warm phase gains mass via cooling of the intermediate phase, while momentum transfer occurs from the hot ($T>5\times10^5\,\rm{K}$) to the warm phase. The large energy flux from the hot outflow that is transferred to the warm and intermediate phases is quickly radiated away. A simple interaction model implies an effective warm cloud size in the fountain flow of a few 100~pc, showing that warm-hot flux exchange mainly involves a few large clouds rather than many small ones.

[12]  arXiv:1911.07876 [pdf, other]

Title: GRB 190114C in the nuclear region of an interacting galaxy -- A detailed host analysis using ALMA, HST and VLT

Authors: A. de Ugarte Postigo, C. C. Thöne, S. Martın, J. Japelj, A. J. Levan, M. J. Michałowski, J. Selsing, D. A. Kann, S. Schulze, J. T. Palmerio, S. D. Vergani, N. R. Tanvir, K. Bensch, S. Covino, V. D'Elia, M. De Pasquale, A. S. Fruchter, J. P. U. Fynbo, D. Hartmann, K. E. Heintz, A. J. van der Horst, L.Izzo, P. Jakobsson, K. C. Y. Ng, D. A. Perley, A. Rossi, B. Sbarufatti, R. Salvaterra, R. Sánchez-Ramírez, D. Watson, D. Xu

Comments: A&A, in press, 11 pages

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)

GRB 190114C is the first GRB for which the detection of very-high energy emission up to the TeV range has been reported. It is still unclear whether environmental properties might have contributed to the production of these very high-energy photons, or if it is solely related to the released GRB emission. The relatively low redshift of the GRB (z=0.425) allows us to study the host galaxy of this event in detail, and to potentially identify idiosyncrasies that could point to progenitor characteristics or environmental properties responsible for such a unique event. We use ultraviolet, optical, infrared and submillimetre imaging and spectroscopy obtained with HST, VLT and ALMA to obtain an extensive dataset on which the analysis of the host galaxy is based. The host system is composed of a close pair of interacting galaxies (Delta v = 50 km s^-1), both of which are well-detected by ALMA in CO(3-2). The GRB occurred within the nuclear region (~170 pc from the centre) of the less massive but more star-forming galaxy of the pair. The host is more massive (log(M/M_odot)=9.3) than average GRB hosts at that redshift and the location of the GRB is rather unique. The enhanced star-formation rate was probably triggered by tidal interactions between the two galaxies. Our ALMA observations indicate that both host galaxy and companion have a high molecular gas fraction, as has been observed before in interacting galaxy pairs. The location of the GRB within the core of an interacting galaxy with an extinguished line-of-sight is indicative of a denser environment than typically observed for GRBs and could have been crucial for the generation of the very-high-energy photons that were observed.

[13]  arXiv:1911.07878 [pdf, other]

Title: The Three Hundred Project: correcting for the hydrostatic-equilibrium mass bias in X-ray and SZ surveys

Authors: S. Ansarifard, E. Rasia, V. Biffi, S. Borgani, W. Cui, M. De Petris, K. Dolag, S. Ettori, S.M.S. Movahed, G. Murante, G. Yepes

Comments: 21 pages, 17 figure, recommended for publication in A&A

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)

Accurate and precise measurements of masses of galaxy clusters are key to derive robust constraints on cosmological parameters. Rising evidence from observations, however, confirms that X-ray masses, obtained under the assumption of hydrostatic equilibrium, might be underestimated, as previously predicted by cosmological simulations.
We analyse more than 300 simulated massive clusters, from `The Three Hundred Project', and investigate the connection between mass bias and several diagnostics extracted from synthetic X-ray images of these simulated clusters.
We find that the azimuthal scatter measured in 12 sectors of the X-ray flux maps is a statistically significant indication of the presence of an intrinsic (i.e. 3D) clumpy gas distribution. We verify that a robust correction to the hydrostatic mass bias can be inferred when estimates of the gas inhomogeneity from X-ray maps (such as the azimuthal scatter or the gas ellipticity) are combined with the asymptotic external slope of the gas density or pressure profiles, which can be respectively derived from X-ray and millimetric (Sunyaev-Zeldovich effect) observations.
We also obtain that mass measurements based on either gas density and temperature or gas density and pressure result in similar distributions of the mass bias. In both cases, we provide corrections that help reduce both the dispersion and skewness of the mass bias distribution. These are effective even when irregular clusters are included leading to interesting implications for the modelling and correction of hydrostatic mass bias in cosmological analyses of current and future X-ray and SZ cluster surveys.

[14]  arXiv:1911.07886 [pdf, ps, other]

Title: BiHalofit: A new fitting formula of non-linear matter bispectrum

Authors: Ryuichi Takahashi, Takahiro Nishimichi, Toshiya Namikawa, Atsushi Taruya, Issha Kayo, Ken Osato, Yosuke Kobayashi, Masato Shirasaki

Comments: 20 pages, 14 figures, submitted to ApJ

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)

We provide an accurate fitting formula of the matter bispectrum in the non-linear regime calibrated by high-resolution cosmological $N$-body simulations for $41$ $w$CDM models around the Planck 2015 best-fit parameters. Our fitting function assumes a similar parameterization as in Halofit for the non-linear matter power spectrum and so is named BiHalofit. The simulation volume is large enough ($> 10 \, {\rm Gpc}^3$) to cover almost all measurable triangle configurations of bispectrum in the universe. Our formula can reproduce the matter bispectrum within $10 \, (15) \, \%$ accuracy for wavenumber $k< 3 \, (10) \, h \, {\rm Mpc}^{-1}$ at redshifts $z=0-3$ for the Planck 2015 model. We also provide a fitting formula to correct baryonic effects such as radiative cooling and active galactic nuclei feedback based on the latest hydrodynamical simulation, IllustrisTNG. Further, we show that our new formula provides more accurate predictions for the weak lensing bispectrum than the existing fitting formulas. The formula would be quite useful for current and future weak lensing surveys and cosmic microwave background lensing experiments.

[15]  arXiv:1911.07889 [pdf, other]

Title: The Search for Planet and Planetesimal Transits of White Dwarfs with the Zwicky Transient Facility

Authors: Keaton J. Bell

Comments: 4 pages, 3 figures; contributed to the Proceedings of IAU Symposium No. 357, "White Dwarfs as Probes of Fundamental Physics and Tracers of Planetary, Stellar, and Galactic Evolution," held in Hilo, HI, 21-25 October 2019

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

Planetary materials orbiting white dwarf stars reveal the ultimate fate of the planets of the Solar System and all known transiting exoplanets. Observed metal pollution and infrared excesses from debris disks support that planetary systems or their remnants are common around white dwarf stars; however, these planets are difficult to detect since a very high orbital inclination angle is required for a small white dwarf to be transited, and these transits have very short (minute) durations. The low odds of catching individual transits could be overcome by a sufficiently wide and fast photometric survey. I demonstrate that, by obtaining over 100 million images of white dwarf stars with 30-second exposures in its first three years, the Zwicky Transient Facility (ZTF) is likely to record the first exoplanetary transits of white dwarfs, as well as new systems of transiting, disintegrating planetesimals. In these proceedings, I describe my project strategy to discover these systems using the ZTF data.

[16]  arXiv:1911.07897 [pdf]

Title: Resonant Kuiper Belt Objects -- a Review

Authors: Renu Malhotra

Comments: Based on an invited review lecture at the 2018 AOGS conference

Journal-ref: Geosci. Lett. (2019) 6:12

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Our understanding of the history of the solar system has undergone a revolution in recent years, owing to new theoretical insights into the origin of Pluto and the discovery of the Kuiper belt and its rich dynamical structure. The emerging picture of dramatic orbital migration of the planets driven by interaction with the primordial Kuiper belt is thought to have produced the final solar system architecture that we live in today. This paper gives a brief summary of this new view of our solar system's history, and reviews the astronomical evidence in the resonant populations of the Kuiper belt.

[17]  arXiv:1911.07898 [pdf, other]

Title: Large Scale Dynamo in a Primordial Accretion Flow -- An Interpretation from Hydrodynamic Simulation

Authors: Wei-Ting Liao, Matthew Turk, Hsi-Yu Schive

Subjects: Astrophysics of Galaxies (astro-ph.GA)

Without an existing large scale coherent magnetic field in the early Universe, Population III (PopIII) stars would likely rotate at or near break-up speed. In this work, focusing on the accretion phase of PopIII stars, we investigate the possibility of generating a coherent magnetic field through large scale dynamo processes, as well as the corresponding field saturation level. Using results from hydrodynamic simulations, we demonstrate that primordial accretion disks are turbulent with a Shakura-Sunyaev disk parameter $\alpha_{ss} \gtrsim 10^{-3}$, and evidence helical turbulence with a dynamo number $\vert D_{\alpha \Omega} \vert \gg 10$. The presence of helical turbulence at these levels allows large scale dynamo modes to grow, and the saturation level is determined by the amount of net helicity remaining in the dynamo-active regions (a.k.a. the quenching problem). %We demonstrate that the magnetic field can reach approximate equipartition, with $B/B_{\rm eq} \sim 3$, indicating that the dynamo quenching problem could be alleviated through an accretion flow. We demonstrate that, if the accretion could successfully alleviate the quenching problem, the magnetic field can reach approximate equipartition with $B/B_{\rm eq} \sim 3$.

[18]  arXiv:1911.07903 [pdf, ps, other]

Title: A Holistic and Probabilistic Approach to the Ground-based Data of HAT-P-19 System

Authors: Ozgur Basturk, Selcuk Yalcinkaya, Ekrem M. Esmer, Taner Tanriverdi, Burak Keten

Comments: 13 pages, 12 figures, 5 tables, Submitted to the Monthly Notices of the Royal Astronomical Society (Nov 5, 2019)

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

We update the fundamental physical and orbital properties of the transiting hot-Saturn type exoplanet HAT-P-19b and its host star HAT-P-19 as a result of the global modeling of our high-precision transit light curves, an archive spectrum, radial velocity observations, brightness values from broadband photometry in different passbands, and the precise distance of the system derived from its Gaia parallax. We collected all the light curves obtained with ground-based photometry by amateur and professional observers, measured mid-transit times, analyzed their differences from calculated transit timings based on reference ephemeris information, which we update as a result. We haven't found any periodicity in the residuals of a linear trend, which we attribute to the accumulation of uncertainties in the reference mid-transit time and the orbital period. We discuss the potential origins of the variation in transit timings briefly and find stellar activity as the most likely cause. Finally, we comment on the scenarios describing the formation and migration of this hot-Saturn type exoplanet with a bloated atmosphere yet a small core, although it is orbiting a metal-rich ([Fe / H] = 0.24 dex) host star based on the planetary, orbital, and stellar parameters of the system that we derived from our global model, the age and the evolutionary history of the star.

[19]  arXiv:1911.07911 [pdf, other]

Title: The Growth of Brightest Cluster Galaxies and Intracluster Light Over the Past Ten Billion Years

Authors: Tahlia DeMaio, Anthony H. Gonzalez, Ann Zabludoff, Dennis Zaritsky, Greg Aldering, Mark Brodwin, Thomas Connor, Megan Donahue, Brian Hayden, John S. Mulchaey, Saul Perlmutter, S. A. Stanford

Comments: Accepted to MNRAS, 9 pages, 6 figures

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We constrain the evolution of the brightest cluster galaxy plus intracluster light (BCG+ICL) using an ensemble of 42 galaxy groups and clusters that span redshifts of z = 0.05-1.75 and masses of $M_{500,c}=2\times10^{13}-10^{15}$ M$_\odot$ Specifically, we measure the relationship between the BCG+ICL stellar mass $M_\star$ and $M_{500,c}$ at projected radii 10 < r < 100 kpc for three different epochs. At intermediate redshift (z = 0.40), where we have the best data, we find $M_\star\propto M_{500,c}^{0.48\pm0.06}$. Fixing the exponent of this power law for all redshifts, we constrain the normalization of this relation to be $2.08\pm0.21$ times higher at z = 0.40 than at high redshift (z = 1.55). We find no change in the relation from intermediate to low redshift (z = 0.10). In other words, for fixed $M_{500,c}$, $M_\star$ at 10 < r < 100 kpc increases from z = 1.55 to z = 0.40 and not significantly thereafter. Theoretical models predict that the physical mass growth of the cluster from z = 1.5 to z = 0 within $r_{500,c}$ is a factor of 1.4, excluding evolution due to definition of $r_{500,c}$. We find that $M_\star$ within the central 100 kpc increases by a factor of 3.8 over the same period. Thus, the growth of $M_\star$ in this central region is more than a factor of two greater than the physical mass growth of the cluster as a whole. Furthermore, the concentration of the BCG+ICL stellar mass, defined by the ratio of stellar mass within 10 kpc to the total stellar mass within 100 kpc, decreases with increasing $M_{500,c}$ at all redshift. We interpret this result as evidence for inside-out growth of the BCG+ICL over the past ten Gyrs, with stellar mass assembly occuring at larger radii at later times.

[20]  arXiv:1911.07946 [pdf, ps, other]

Title: Inward Bound: The incredible journey of massive black holes as they pair and merge; I. The effect of mass ratio in flattened rotating galactic nuclei

Authors: Fazeel Mahmood Khan, Muhammad Awais Mirza, Kelly Holley-Bockelmann

Comments: Accepted for publication in MNRAS

Subjects: Astrophysics of Galaxies (astro-ph.GA)

Understanding how supermassive black holes (SMBHs) pair and merge helps to inform predictions of off-center, dual, and binary AGN, and provides key insights into how SMBHs grow and co-evolve with their galaxy hosts. As the loudest known gravitational wave source, binary SMBH mergers also hold centerstage for the Laser Interferometer Space Antenna (LISA), a joint ESA/NASA gravitational wave observatory set to launch in 2034. Here, we continue our work to characterize SMBH binary formation and evolution through increasingly more realistic high resolution direct $N$-body simulations, focusing on the effect of SMBH mass ratio, orientation, and eccentricity within a rotating and flattened stellar host. During the dynamical friction phase, we found a prolonged orbital decay for retrograde SMBHs and swift pairing timescales for prograde SMBHs compared to their counterparts in non-rotating models, an effect that becomes more pronounced for smaller mass ratios $M_{\rm sec}/M_{\rm prim} = q$. During this pairing phase, the eccentricity dramatically increases for retrograde configurations, but as the binary forms, the orbital plane flips so that it is almost perfectly prograde, which stifles the rapid eccentricity growth. In prograde configurations, SMBH binaries form and remain at comparatively low eccentricities. As in our prior work, we note that the center of mass of a prograde SMBH binary itself settles into an orbit about the center of the galaxy. Since even the initially retrograde binaries flip their orbital plane, we expect few binaries in rotating systems to reside at rest in the dynamic center of the host galaxy, though this effect is smaller as $q$ decreases.

[21]  arXiv:1911.07950 [pdf, ps, other]

Title: Covariant Radiative Transfer for Black Hole Spacetimes

Authors: Shane W. Davis, Charles F. Gammie

Comments: 29 pages, 0 figures

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

It has now become possible to study directly, via numerical simulation, the evolution of relativistic, radiation-dominated flows around compact objects. With this in mind we set out explicitly covariant forms of the radiative transfer equation that are suitable for numerical integration in curved spacetime or flat spacetime in curvilinear coordinates. Our work builds on and summarizes in consistent form earlier work by Lindquist, Thorne, Morita and Kaneko, and others. We give explicitly the basic equations in spherical-polar coordinates for Minkowski space and the Kerr spacetime in Kerr-Schild coordinates.

[22]  arXiv:1911.07957 [pdf, other]

Title: Stability of exoplanetary systems retrieved from scalar time series

Authors: Tamas Kovacs

Comments: 19 pages, 20 figures, accepted for publication in mnras

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Chaotic Dynamics (nlin.CD)

We propose a novel method applied to extrasolar planetary dynamics to describe the system stability. The observations in this field serve the measurements mainly of radial velocity, transit time, and/or celestial position. These scalar time series are used to build up the high-dimensional phase space trajectory representing the dynamical evolution of planetary motion. The framework of nonlinear time series analysis and Poincar\'e recurrences allows us to transform the obtained univariate signals into complex networks whose topology carries the dynamical properties of the underlying system. The network-based analysis is able to distinguish the regular and chaotic behaviour not only for synthetic inputs but also for noisy and irregularly sampled real world observations. The proposed scheme does not require neither n-body integration nor best fitting planetary model to perform the stability investigation, therefore, the computation time can be reduced drastically compared to those of the standard numerical methods.

[23]  arXiv:1911.07973 [pdf, other]

Title: Superdiffusive Stochastic Fermi Acceleration in Space and Energy

Authors: Nikos Sioulas, Heinz Isliker, Loukas Vlahos, Argyris Koumtzis, Theophilos Pisokas

Comments: 11 pages, 8 figures, accepted for publication in MNRAS

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)

We analyze the transport properties of charged particles (ions and electrons) interacting with randomly formed magnetic scatterers (e.g.\ large scale local ``magnetic fluctuations'' or ``coherent magnetic irregularities'' usually present in strongly turbulent plasmas), using the energization processes proposed initially by Fermi in 1949. The scatterers are formed by large scale local fluctuations ($\delta B/B \approx 1$) and are randomly distributed inside the unstable magnetic topology. We construct a 3D grid on which a small fraction of randomly chosen grid points are acting as scatterers. In particular, we study how a large number of test particles are accelerated and transported inside a collection of scatterers in a finite volume. Our main results are: (1) The spatial mean-square displacement $<(\Delta r)^2>$ inside the stochastic Fermi accelerator is superdiffusive, $<(\Delta r)^2> \sim t^{a_{r}},$ with $a_r \sim 1.2-1.6$, for the high energy electrons with kinetic energy $(W)$ larger than $1 MeV$, and it is normal ($a_r=1$) for the heated low energy $(W< 10 keV)$ electrons. (2) The transport properties of the high energy particles are closely related with the mean-free path that the particles travel in-between the scatterers ($\lambda_{sc}$). The smaller $\lambda_{sc}$ is, the faster the electrons and ions escape from the acceleration volume. (3) The mean displacement in energy $<\Delta W> \sim t^{a_{W}}$ is strongly enhanced inside the acceleration volume $(a_W=1.5- 2.5)$ for the high energy particles compared to the thermal low energy particles ($a_W=0.4$), i.e.\ high energy particles undergo an enhanced systematic gain in energy.(4) The mean-square displacement in energy $<W^2>$ is superdiffusive for the high energy particles and normal for the low energy, heated particles.

[24]  arXiv:1911.08047 [pdf, other]

Title: Particle Physics with the Cosmic Microwave Background with SPT-3G

Authors: J. S. Avva, P. A. R. Ade, Z. Ahmed, A. J. Anderson, K. Aylor, R. Basu Thakur, A. N. Bender, B. A. Benson, L. E. Bleem, S. Bocquet, L. Bryant, J. E. Carlstrom, F. W. Carter, T. W. Cecil, C. L. Chang, T. M. Crawford, A. Cukierman, T. de Haan, J. Ding, M. A. Dobbs, S. Dodelson, D. Dutcher, W. Everett, K. R. Ferguson, A. Foster, J. Gallicchio, A. E. Gambrel, R. W. Gardner, J. C. Groh, S. Guns, N. W. Halverson, A. H. Harke-Hosemann, N. L. Harrington, J. W. Henning, G. P. Holder, W. L. Holzapfel, D. Howe, N. Huang, K. D. Irwin, O. B. Jeong, M. Jonas, A. Jones, T. S. Khaire, L. Knox, A. M. Kofman, M. Korman, D. L. Kubik, S. Kuhlmann, C.-L. Kuo, A. T. Lee, A. E. Lowitz, S. S. Meyer, D. Michalik, J. Montgomery, A. Nadolski, T. Natoli, H. Nguyen, G. I. Noble, V. Novosad, S. Padin, Z. Pan, P. Paschos, et al. (26 additional authors not shown)

Comments: 6 pages, 2 figures, TAUP 2019

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

The cosmic microwave background (CMB) encodes information about the content and evolution of the universe. The presence of light, weakly interacting particles impacts the expansion history of the early universe, which alters the temperature and polarization anisotropies of the CMB. In this way, current measurements of the CMB place interesting constraints on the neutrino energy density and mass, as well as on the abundance of other possible light relativistic particle species. We present the status of an on-going 1500 sq. deg. survey with the SPT-3G receiver, a new mm-wavelength camera on the 10-m diameter South Pole Telescope (SPT). The SPT-3G camera consists of 16,000 superconducting transition edge sensors, a 10x increase over the previous generation camera, which allows it to map the CMB with an unprecedented combination of sensitivity and angular resolution. We highlight projected constraints on the abundance of sterile neutrinos and the sum of the neutrino masses for the SPT-3G survey, which could help determine the neutrino mass hierarchy.

[25]  arXiv:1911.08057 [pdf, other]

Title: Characterization of a 15 $μm$ Cutoff HgCdTe Detector Array for Astronomy

Authors: Mario S. Cabrera, Craig W. McMurtry, William J. Forrest, Judith L. Pipher, Meghan L. Dorn, Donald Lee

Journal-ref: J. Astron. Telesc. Instrum. Syst. 6(1), 011004 (2020)

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

The University of Rochester infrared detector group is working together with Teledyne Imaging Sensors to develop HgCdTe 15 $\mu m$ cutoff wavelength detector arrays for future space missions. To reach the 15 $\mu m$ cutoff goal, we took an intermediate step by developing four $\sim$13 $\mu m$ cutoff wavelength arrays to identify any unforeseen effects related to increasing the cutoff wavelength from the extensively characterized 10 $\mu m$ cutoff wavelength detector arrays developed for the NEOCam mission. The characterization of the $\sim$13 $\mu m$ cutoff wavelength HgCdTe arrays at the University of Rochester allowed us to determine the key dark current mechanisms that limit the performance of these HgCdTe detector arrays at different temperatures and bias when the cutoff wavelength is increased. We present initial dark current and well depth measurements of a 15 $\mu m$ cutoff array which shows dark current values two orders of magnitude smaller at large reverse bias than would be expected from our previous best structures.

[26]  arXiv:1911.08064 [pdf, other]

Title: The Acceleration and Confinement of Energetic Electrons by a Termination Shock in a Magnetic Trap: An Explanation for Nonthermal Loop-top Sources during Solar Flares

Authors: Xiangliang Kong, Fan Guo, Chengcai Shen, Bin Chen, Yao Chen, Sophie Musset, Lindsay Glesener, Peera Pongkitiwanichakul, Joe Giacalone

Comments: submitted to ApJL

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Space Physics (physics.space-ph)

Nonthermal loop-top sources in solar flares are the most prominent observational signature that suggests energy release and particle acceleration in the solar corona. Although several scenarios for particle acceleration have been proposed, the origin of the loop-top sources remains unclear. Here we present a model that combines a large-scale magnetohydrodynamic simulation of a two-ribbon flare with a particle acceleration and transport model for investigating electron acceleration by a fast-mode termination shock at the looptop. Our model provides spatially resolved electron distribution that evolves in response to the dynamic flare geometry. We find a concave-downward magnetic structure located below the flare termination shock, induced by the fast reconnection downflows. It acts as a magnetic trap to confine the electrons at the looptop for an extended period of time. The electrons are energized significantly as they cross the shock front, and eventually build up a power-law energy spectrum extending to hundreds of keV. We suggest that this particle acceleration and transport scenario driven by a flare termination shock is a viable interpretation for the observed nonthermal loop-top sources.

[27]  arXiv:1911.08070 [pdf, other]

Title: Constraints on Lorentz invariance violation from HAWC observations of gamma rays above 100 TeV

Authors: HAWC Collaboration: A. Albert, R. Alfaro, C. Alvarez, J.R. Angeles Camacho, J.C. Arteaga-Velázquez, K.P. Arunbabu, D. Avila Rojas, H.A. Ayala Solares, V. Baghmanyan, E. Belmont-Moreno, S.Y. BenZvi, C. Brisbois, K.S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, U. Cotti, J. Cotzomi, S. Coutiño de León, E. De la Fuente, C. de León, B.L. Dingus, M.A. DuVernois, J.C. Díaz-Vélez, R.W. Ellsworth, K. Engel, C. Espinoza, H. Fleischhack, N. Fraija, A. Galván-Gámez, D. Garcia, J.A. García-González, F. Garfias, M.M. González, J.A. Goodman, J.P. Harding, S. Hernandez, B. Hona, D. Huang, F. Hueyotl-Zahuantitla, P. Hüntemeyer, A. Iriarte, V. Joshi, A. Lara, W.H. Lee, H. León Vargas, J.T. Linnemann, A.L. Longinotti, et al. (44 additional authors not shown)

Comments: 9 pages, 3 figures. Submitted to journal

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

Due to the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal LIV enables the decay of photons at high energy. The High Altitude Water Cherenkov (HAWC) Observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to $2.2\times10^{31}$ eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.

[28]  arXiv:1911.08093 [pdf, ps, other]

Title: ASASSN-14ho: Longest-period Dwarf Nova with Multiple Rebrightenings

Authors: Taichi Kato (Kyoto U)

Comments: 4 pages, 1 figure, accepted for publication in PASJ

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)

The post-outburst rebrightening phenomenon in dwarf novae and X-ray novae is still one of the most challenging subjects for theories of accretion disks. It has been widely recognized that post-outburst rebrightenings are a key feature of WZ Sge-type dwarf novae, which predominantly have short ($\lesssim$0.06 d) orbital periods. I found four post-outburst rebrightenings in ASASSN-14ho during its 2014 outburst, whose orbital period has recently measured to be exceptionally long [0.24315(10) d]. Using the formal solution of the radial velocity study in the literature, I discuss the possibility that this object can be an SU UMa-type dwarf nova near the stability border of the 3:1 resonance despite its exceptionally long orbital period. Such objects are considered to be produced if mass transfer occurs after the secondary has undergone significant nuclear evolution and they may be hidden in a significant number among dwarf novae showing multiple post-outburst rebrightenings.

[29]  arXiv:1911.08096 [pdf, other]

Title: Searching for the possible signal of the photon-axionlike particle oscillation in the combined GeV and TeV spectra of supernova remnants

Authors: Zi-Qing Xia, Yun-Feng Liang, Lei Feng, Qiang Yuan, Yi-Zhong Fan, Jian Wu

Comments: 11 pages, 8 figures, Accepted into Physical Review D

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)

The conversion between photons and axionlike particles (ALPs) in the Milky Way magnetic field could result in the detectable oscillation phenomena in $\gamma$-ray spectra of Galactic sources. In this work, the GeV (Fermi-LAT) and TeV (MAGIC/VERITAS/H.E.S.S.) data of three bright supernova remnants (SNRs, ie. IC443, W51C and W49B) have been adopted together to search such the oscillation effect. Different from our previous analysis of the sole Fermi-LAT data of IC443, we do not find any reliable signal for the photon-ALP oscillation in the joint broadband spectrum of each SNR. The reason for the inconsistence is that in this work we use the latest revision (P8R3) of Fermi-LAT data, updated diffuse emission templates and the new version of the source catalog (4FGL), which lead to some modification of the GeV spectrum of IC443. Then we set constraints on ALP parameters based on the combined analysis of all the three sources. Though these constraints are somewhat weaker than limits from the CAST experiment and globular clusters, they are supportive of and complementary to these other results.

[30]  arXiv:1911.08107 [pdf, other]

Title: The masses of isolated neutron stars inferred from the gravitational redshift measurements

Authors: Shao-Peng Tang, Jin-Liang Jiang, Wei-Hong Gao, Yi-Zhong Fan, Da-Ming Wei

Comments: 8 pages, 7 figures, ApJ accepted

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

For some neutron stars (NSs) in the binary systems, the masses have been accurately measured. While for the isolated neutron stars (INSs), no mass measurement has been reported yet. The situation will change soon thanks to the successful performance of the Neutron Star Interior Composition Explorer (NICER), with which the radius and mass of the isolated PSR J0030+0451 can be simultaneously measured. Anyhow, for most INSs, no mass measurements are possible for NICER because of the observational limitations. Benefited from the recent significant progress made on constraining the equation of state (EoS) of NSs, in this work we propose a way to estimate the masses of the INSs with the measured gravitational redshifts. We apply our method to RX J1856.5-3754, RX J0720.4-3125, and RBS 1223, three members of "The Magnificent Seven" (M7), and estimate their masses to be $1.24_{-0.29}^{+0.29}M_{\odot}$, $1.23_{-0.05}^{+0.10}M_{\odot}$, and $1.08_{-0.11}^{+0.20}M_{\odot}$, respectively. These masses are consistent with that of binary neutron star (BNS) systems, suggesting no evidence for experiencing significant accretion of these isolated objects.

[31]  arXiv:1911.08124 [pdf, other]

Title: Candidate radio supernova remnants observed by the GLEAM survey over $345^\circ < l < 60^\circ$ and $180^\circ < l < 240^\circ$

Authors: Natasha Hurley-Walker, Bryan M. Gaensler, Denis A. Leahy, Miroslav D. Filipovic, Paul J. Hancock, Thomas M. O. Franzen, Andre R. Offringa, Joseph R. Callingham, Luke Hindson, Chen Wu, Martin E. Bell, Bi-Qing For, Melanie Johnston-Hollitt, Anna D. Kapinska, John Morgan, Tara Murphy, Benjamin McKinley, Pietro Procopio, Lister Staveley-Smith, Randall B. Wayth, Cathie Q. Zheng

Comments: 39 pages, 60 figures, 2 tables, accepted to PASA

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)

We examined the latest data release from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey covering $345^\circ < l < 60^\circ$, $180^\circ < l < 240^\circ$, using these data and that of the Widefield Infrared Survey Explorer to follow up proposed candidate Supernova Remnants from other sources. Of the 101 candidates proposed in the region, we are able to definitively confirm ten as SNRs, tentatively confirm two as SNRs, and reclassify five as Hii regions. A further two are detectable in our images but difficult to classify; the remaining 82 are undetectable in these data. We also investigated the 18 unclassified Multi-Array Galactic Plane Imaging Survey (MAGPIS) candidate SNRs, newly confirming three as SNRs, reclassifying two as Hii regions, and exploring the unusual spectra and morphology of two others.

[32]  arXiv:1911.08126 [pdf, other]

Title: New candidate radio supernova remnants detected in the GLEAM survey over $345^\circ < l < 60^\circ$, $180^\circ < l < 240^\circ$

Authors: Natasha Hurley-Walker, Miroslav D. Filipovic, Bryan M. Gaensler, Denis A. Leahy, Paul J. Hancock, Thomas M. O. Franzen, Andre R. Offringa, Joseph R. Callingham, Luke Hindson, Chen Wu, Martin E. Bell, Bi-Qing For, Melanie Johnston-Hollitt, Anna D. Kapinska, John Morgan, Tara Murphy, Benjamin McKinley, Pietro Procopio, Lister Staveley-Smith, Randall B. Wayth, Cathie Q. Zheng

Comments: 34 pages, 83 figures, 2 tables, accepted to PASA

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)

We have detected 27 new supernova remnants (SNRs) using a new data release of the GLEAM survey from the Murchison Widefield Array (MWA) telescope, including the lowest surface-brightness SNR ever detected, G0.1-9.7. Our method uses spectral fitting to the radio continuum to derive spectral indices for 26/27 candidates, and our low-frequency observations probe a steeper-spectrum population than previously discovered. None of the candidates have coincident Wide-field Infrared Survey Explorer mid-IR emission, further showing that the emission is non-thermal. Using pulsar associations we derive physical properties for six candidate SNRs, finding G0.1-9.7 may be younger than 10kyr. 60% of the candidates subtend areas larger than 0.2deg$^{2}$ on the sky, compared to $<25$% of previously-detected SNRs. We also make the first detection of two SNRs in the Galactic longitude range $220^\circ-240^\circ$.

[33]  arXiv:1911.08127 [pdf, other]

Title: GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey II: Galactic Plane $345^\circ < l < 67^\circ$, $180^\circ < l < 240^\circ$

Authors: Natasha Hurley-Walker, Paul J. Hancock, Thomas M. O. Franzen, Joseph R. Callingham, Andre R. Offringa, Luke Hindson, Chen Wu, Martin E. Bell, Bi-Qing For, Bryan M. Gaensler, Melanie Johnston-Hollitt, Anna D. Kapinska, John Morgan, Tara Murphy, Benjamin McKinley, Pietro Procopio, Lister Staveley-Smith, Randall B. Wayth, Cathie Q. Zheng

Comments: 14 pages, 9 figures, 2 tables, accepted to PASA

Subjects: Astrophysics of Galaxies (astro-ph.GA); Instrumentation and Methods for Astrophysics (astro-ph.IM)

This work makes available a further 2,860deg$^2$ of the GLEAM survey, covering half of the accessible Galactic Plane, across twenty frequency bands sampling $72-231$MHz, with resolution $4'-2'$. Unlike previous GLEAM data releases, we used multi-scale clean to better deconvolve large-scale Galactic structure. For the Galactic longitude ranges $345^\circ < l < 67^\circ$, $180^\circ < l < 240^\circ$, we provide a compact source catalogue of 22,037 components selected from a 60-MHz bandwidth image centred at 200-MHz, with RMS noise $\approx10-20$mJy beam$^{-1}$ and position accuracy better than $2"$. The catalogue has a completeness of 50% at $\approx120$mJy, and a reliability of 99.86%. It covers Galactic latitudes $1^\circ\leq|b|\leq10^\circ$ toward the Galactic Centre and $|b|\leq10^\circ$ for other regions, and is available from Vizier; images covering $|b|\leq10^\circ$ for all longitudes are made available on the GLEAM VO server and SkyView.

[34]  arXiv:1911.08131 [pdf, ps, other]

Title: Systematic Regularity of Solar Coronal Rotation During the Time Interval 1939-2019

Authors: L. H. Deng, X. J. Zhang, H. Deng, Y. Mei, F. Wang

Comments: 9 Pages, 12 figures, Accepted by MNRAS

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

Temporal variation of the solar coronal rotation appears to be very complex and its relevances to the eleven-year solar activity cycle are still unclear. Using the modified coronal index for the time interval from 1939 January 1 to 2019 May 31, the systematic regularities of the solar coronal rotation are investigated. Our main findings are as follows: (1) from a global point of view, the synodic coronal rotation period with a value of 27.5 days is the only significant period at the periodic scales shorter than 64 days; (2) the coronal rotation period exhibit an obviously decreasing trend during the considered time interval, implying the solar corona accelerates its global rotation rate in the long run; (3) there exist significant periods of 3.25, 6.13, 9.53, and 11.13 years in the period length of the coronal rotation, providing an evidence that the coronal rotation should be connected with the quasi-biennial oscillation, the eleven-year solar cycle, and the 22-year Hale cycle (or the magnetic activity reversal); and (4) the phase relationship between the coronal rotation period and the solar magnetic activity is not only time-dependent but also frequency-dependent. For a small range around the 11- year cycle band, there is a systematic trend in the phase, and the small mismatch in this band brings out the phase to drift. The possible mechanism for the above analysis results is discussed.

[35]  arXiv:1911.08198 [pdf, other]

Title: Nature of $γ$-ray variability in blazars

Authors: Gopal Bhatta, Niraj Dhital

Comments: 28 pages, 12 figures

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

We present an in-depth and systematic analysis of a sample of 20 powerful blazars, including 12 BL Lacs and 8 flat spectrum radio quasars, utilizing Fermi/LAT observations from the period 2008--2018 using various analysis tools such as flux distribution, symmetry analysis, and time series analysis. Results show that blazars with steeper $\gamma$-ray spectral indexes are found to be more variable; and the $\gamma$-ray flux distribution closely resemble both normal and lognormal probability distribution functions. The statistical variability properties of the sources as studied by power spectral density analysis are consistent with flicker noise ($P(\nu)\propto1/\nu$) -- an indication of long-memory processes at work. Statistical analysis of the distribution of flux rise and decay rates in the light curves of the sources, aimed at distinguishing between particle acceleration and energy dissipation timescales, counter-intuitively suggests that both kinds of rates follow a similar distribution and the derived mean variability timescales are in the order of a few weeks. The corresponding emission region size is used to constrain location of $\gamma$-ray production sites in the sources to be a few parsecs. Additionally, using Lomb-Scargle periodogram aided with extensive Monte Carlo simulations, we detected year timescale quasi-periodic oscillations in the sources S5 0716+714, Mrk 421, ON +325, PKS 1424-418 and PKS 2155-304; and the detection significance was computed taking proper account of the red-noise and other artifacts inherent in the observations. We explain our results in the light of current blazar models with relativistic shocks propagating down the jet viewed close to the line of sight.

[36]  arXiv:1911.08205 [pdf, ps, other]

Title: Integrating the VO Framework in the EOSC

Authors: Marco Molinaro, Mark Allen, Sara Bertocco, Catherine Boisson, François Bonnarel, Margarida Castro Neves, Markus Demleitner, Françoise Genova, Dave Morris, André Schaaff, Giuliano Taffoni, Stelios Voutsinas

Comments: 4 pages, 2 figures, ADASS XXIX proceedings

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

The European Open Science Cloud (EOSC) is in its early stages, but already some aspects of the EOSC vision are starting to become reality, for example the EOSC portal and the development of metadata catalogues. In the astrophysical domain already exists an open approach to science data: the Virtual Observatory view put in place by the International Virtual Observatory Alliance (IVOA) architecture of standards. The ESCAPE (European Science Cluster of Astronomy & Particle physics ESFRI research infrastructures) project has, among its tasks, to demonstrate that the VO architecture can be integrated within the EOSC building one and to provide guidelines to ESFRI partners (European Strategy Forum on Research Infrastructures) in doing this. This contribution reports on the progress of this integration after the first months of work inside ESCAPE.

[37]  arXiv:1911.08228 [pdf, other]

Title: High redshift constraints on dark energy models and tension with the flat LambdaCDM model

Authors: M. Demianski, E.Piedipalumbo, D.Sawant, L. Amati

Comments: 27 pages, 11 figures submitted to JCAP

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

So far large and different data sets revealed the accelerated expansion rate of the Universe, which is usually explained in terms of dark energy. The nature of dark energy is not yet known, and several models have been introduced: a non zero cosmological constant, a potential energy of some scalar field, effects related to the non homogeneous distribution of matter, or effects due to alternative theories of gravity. In [1, 2] a tension with the flat LambdaCDM model has been discovered using a high-redshift Hubble diagram of supernovae, quasars, and gamma-ray bursts. Here we use Union2 type Ia supernovae (SNIa) and Gamma Ray Bursts (GRB) Hubble diagram, and a set of direct measurements of the Hubble parameter to explore different dark energy models. We use the Chevallier-Polarski-Linder (CPL) parametrization of the dark energy equation of state (EOS), a minimally coupled quintessence scalar field, and, finally, we consider models with dark energy at early times (EDE). We perform a statistical analysis based on the Markov chain Monte Carlo (MCMC) method, and explore the probability distributions of the cosmological parameters for each of the competing models. We apply the Akaike Information Criterion (AIC) to compare these models: our analysis indicates that an evolving dark energy, described by a scalar field with exponential potential is favoured by observational data.

[38]  arXiv:1911.08232 [pdf, other]

Title: Low-redshift constraints on homogeneous and isotropic universes with torsion

Authors: C. M. J. Marques, C. J. A. P. Martins

Comments: 11 pages, 5 figures; Physics of the Dark Universe (in press)

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)

One of the possible extensions of Einstein's General Theory of Relativity consists in allowing for the presence of spacetime torsion. The form of the underlying torsion tensor can be chosen such that the homogeneity and isotropy of Friedmann-Lemaitre-Robertson-Walker universes is preserved, and it has been recently suggested that such universes may undergo accelerating phases. We use recent low-redshift data, coming from Type Ia Supernova and Hubble parameter measurements, to phenomenologically constrain this class of models under the so-called steady-state torsion assumption of a constant fractional contribution of torsion to the volume expansion. We start by considering models without a cosmological constant (where torsion itself would be expected to yield the current acceleration of the universe) finding, in agreement with other recent works, that these are strongly disfavoured by the data. We then treat these models as one-parameter extensions of $\Lambda$CDM, constraining the relative contribution of torsion to the level of a few percent in appropriate units. Finally, we briefly discuss how these constraints may be improved by forthcoming low-redshift data and check the robustness of our results by studying an alternative to the steady-state torsion parametrization.

[39]  arXiv:1911.08235 [pdf, ps, other]

Title: Role of lunar laser ranging in realization of terrestrial, lunar, and ephemeris reference frames

Authors: Dmitry Pavlov

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Three possible applications of lunar laser ranging to space geodesy are studied. First, the determination of daily Earth orientation parameters (UT0 and variation of latitude), which is rarely used nowadays in presence of all-year VLBI, SLR, and GNSS data. The second application is the determination of two (out of three) lunar orientation parameters, i.e. daily corrections to the rotational ephemeris of the Moon. It may be of importance for the future lunar satellite-based navigational systems. The third application is the tie of ephemeris frame (BCRF) to the ICRF. It has been studied before, though in this work it is extensively compared to another realization of the same tie, obtained by spacecraft VLBI observations; also, two different EOP series and two different models of tidal variations of geopotential are applied, with different outcomes on the tie.
The EPM lunar-planetary ephemeris, along with its underlying dynamical model and software, was used to obtain the presented results. All available observations were processed, since the earliest made at the end of 1969 at the McDonald observatory till the end of July 2019 (Matera, Grasse and also Wettzell observatory which began to provide data in 2018). The results and some open questions are discussed.

[40]  arXiv:1911.08273 [pdf, other]

Title: VLT/SINFONI study of black hole growth in high redshift radio-loud quasars from the CARLA survey

Authors: M. Marinello, R.A. Overzier, H.J.A. Röttgering, J.D. Kurk, C. De Breuck, J. Vernet, D. Wylezalek, D. Stern, K.J. Duncan, N. Hatch, N. Kashikawa, Y.-T. Lin, R.S. Nemmen, A. Saxena

Comments: MNRAS, accepted (28 pages, 22 figures)

Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)

We present VLT/SINFONI observations of 35 quasars at 2.1 < z < 3.2, the majority of which were selected from the Clusters Around Radio-Loud AGN (CARLA) survey. CARLA quasars have large CIV-based black hole (BH) masses (M(BH) > 10^9 Msun) and powerful radio emission (P(500MHz) > 27.5 W/Hz). We estimate Ha-based M(BH), finding a scatter of 0.35 dex compared to CIV. We evaluate several recipes for correcting CIV-based masses, which reduce the scatter to 0.24 dex. The radio power of the radio-loud quasars is at most weakly correlated with the interconnected quantities Ha-width, L(5100A) and M(BH), suggesting that it is governed by different physical processes. However, we do find a strong inverse correlation between CIV blueshift and radio power linked to higher Eddington ratios and L(5100A). Under standard assumptions, the BH growth time is longer than the cosmic age for many CARLA quasars, suggesting that they must have experienced more efficient growth in the past. If these BHs were growing from seeds since the epoch of reionization, it is possible that they grew at the Eddington limit like the quasars at z ~ 6-7, and then continued to grow at the reduced rates observed until z ~ 2-3. Finally, we study the relation between M(BH) and environment, finding a weak positive correlation between M(BH) and galaxy density measured by CARLA.

[41]  arXiv:1911.08275 [pdf, other]

Title: Corrfunc: Blazing fast correlation functions with AVX512F SIMD Intrinsics

Authors: Manodeep Sinha, Lehman H. Garrison

Comments: Paper II for the Corrfunc software package, paper I is on arXiv here: arXiv:1911.03545. Appeared in the refereed proceedings for the "Second Workshop on Software Challenges to Exascale Computing"

Journal-ref: Communications in Computer and Information Science: Proceedings of the 'Software Challenges to Exascale Computing' Second Workshop, SCEC 2018, Delhi, India, December 13-14 2018, Vol. 964, pp. 3-20

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA); Data Structures and Algorithms (cs.DS)

Correlation functions are widely used in extra-galactic astrophysics to extract insights into how galaxies occupy dark matter halos and in cosmology to place stringent constraints on cosmological parameters. A correlation function fundamentally requires computing pair-wise separations between two sets of points and then computing a histogram of the separations. Corrfunc is an existing open-source, high-performance software package for efficiently computing a multitude of correlation functions. In this paper, we will discuss the SIMD AVX512F kernels within Corrfunc, capable of processing 16 floats or 8 doubles at a time. The latest manually implemented Corrfunc AVX512F kernels show a speedup of up to $\sim 4\times$ relative to compiler-generated code for double-precision calculations. The AVX512F kernels show $\sim 1.6\times$ speedup relative to the AVX kernels and compare favorably to a theoretical maximum of $2\times$. In addition, by pruning pairs with too large of a minimum possible separation, we achieve a $\sim 5-10\%$ speedup across all the SIMD kernels. Such speedups highlight the importance of programming explicitly with SIMD vector intrinsics for complex calculations that can not be efficiently vectorized by compilers. Corrfunc is publicly available at https://github.com/manodeep/Corrfunc/.

[42]  arXiv:1911.08318 [pdf, other]

Title: First Results from TESS Observations of Comet 46P/Wirtanen

Authors: Tony L. Farnham, Michael S. P. Kelley, Matthew M. Knight, Lori M. Feaga

Comments: 9 pages, 5 figures

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

We report on initial results from 20 days' worth of TESS spacecraft observations of comet 46P/Wirtanen. The long-duration, high-cadence measurements show a 2018 September 26 outburst that exhibited a two-phase, 0.5 mag brightening profile, and may be the best temporally characterized natural outburst ever recorded. Gas velocities from the outburst peaked at 800 m s$^{-1}$, while dust expanded at only 10s of m s$^{-1}$. Coadded images also revealed a previously unreported dust trail that extends beyond the 24$^\circ$ field of view.

[43]  arXiv:1911.08321 [pdf, other]

Title: Evolution of High-energy Particle Distribution in Supernova Remnants

Authors: Houdun Zeng, Yuliang Xin, Qi Fu, Siming Liu

Comments: 3 pages, 4 figures; contribution to the proceedings of "Supernova Remnants II: An Odyssey in Space after Stellar death", 3-8 June 2019, Chania, Grete, Greece

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)

The spectra fits to a sample of 34 supernova remnants (Zeng et al., 2019) are updated. $\gamma$-ray spectra of 20 supernova remnants (SNRs) with a soft TeV spectrum are further analyzed. We found that 17 of them can be fitted in the hadronic scenario with a single power-law ion distribution with an index of $\sim$ 2.6, which is significantly softer than the ion distribution inferred from $\gamma$-ray observations of star-burst galaxies. If Galactic cosmic rays are mostly produced by SNRs, this result suggests that SNRs in star-burst galaxies may never reach the phase with a soft $\gamma$-ray spectra or escape of high-energy particles from SNRs before they reach this phase with a soft $\gamma$-ray spectrum dominates the contribution of SNRs to Galactic cosmic rays.

[44]  arXiv:1911.08325 [pdf]

Title: Fiber modal noise mitigation by a rotating double scrambler

Authors: Gert Raskin, Dmytro Rogozin, Tom Mladenov, Christian Schwab, David Coutts

Comments: SPIE ANZCOP conference, Melbourne 2019

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Fiber modal noise is a performance limiting factor in high-precision radial velocity measurements with multi-mode fiber-fed high-resolution spectrographs. Traditionally, modal noise is mitigated by agitating the fiber, this way redistributing the light that propagates in the fiber over many different modes. However, in case of fibers with only a limited number of modes, e.g. at near-infrared wavelengths or in adaptive-optics assisted systems, this method becomes very inefficient. The strong agitation that would be needed stresses the fiber and can lead to focal ratio degradation. As an alternative approach, we propose to use a classic optical double scrambler and to rotate the scrambler's first fiber end during each exposure. Because of the rotating illumination pattern of the scrambler's second fiber, the modes that are excited vary continuously. This leads to very efficient averaging of the modal pattern at the fiber exit and to a strong reduction of modal noise. In this contribution, we present a prototype design and first laboratory results of the rotating double scrambler.

[45]  arXiv:1911.08330 [pdf]

Title: 5 Years of Defocused Observations of Exoplanet Transits with T100: Timing Perspective

Authors: Ozgur Basturk, Selcuk Yalcinkaya, Burak Keten

Comments: 8 pages, 7 figures, 1 table, presented in 8th Meeting of The Middle East Occultation Timing Association in Istanbul

Journal-ref: Journal of Occultation and Eclipse (JOE), 2018, 2No: 5, 1-8

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Solar and Stellar Astrophysics (astro-ph.SR)

We have been carrying out a program for over five years to observe transits of selected exoplanets with 1-meter Turkish Telescope, T100 (Ba\c{s}t\"urk et al. 2014, 2015), by making use of the well-established defocusing technique (Southworth et al. 2009) to achieve high photometric precision. In this contribution, we review the results of our observing program in timing perspective. The basic idea behind defocusing technique is to have the advantage of posing the detector for longer duration in the observations of bright stars, otherwise observed within very short integration times. Then the effect of the photon noise is diminished, which dominates in the short cadence observations. Longer exposures also help in reducing the noise contribution of the atmospheric scintillation. Noise contributions of the imperfect tracking and flat-fielding are mitigated by integrating over a larger area on the detector as well. Although fewer images can be acquired in a given time, we argue that the timing precision is improved because of better photometric precision. This contribution has been supported by T\"UB\.ITAK-3001 project 116F350.

[46]  arXiv:1911.08331 [pdf]

Title: Transit Timing Variations of Five Transiting Planets

Authors: Ozgur Basturk, Ekrem M. Esmer, Seyma Torun, Selcuk Yalcinkaya, Fadel El Helweh, Ertugrul Karamanli, Mehmet Oncu, H. Ozgur Albayrak, Afra F.M. Akram, Muammer G. Kahraman, Shaad Sufi, Muhammed Uzumcu, Fatemeh Davoudi

Comments: 8 pages, 7 figures, 2 tables, presented in Turkish Physical Society 35th International Physics Conference (this http URL), a four-page version has been submitted and accepted for publication in American Institute of Physics Conference Series

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Instrumentation and Methods for Astrophysics (astro-ph.IM); Solar and Stellar Astrophysics (astro-ph.SR)

Transiting planets provide a unique opportunity to search for unseen additional bodies gravitationally bound to a system. It is possible to detect the motion of the center-of-mass of the observed transiting planet-host star duo due to the gravitational tugs of the unseen bodies from the Roemer delay. In order to achieve the goal, determination of the mid-times of the transits of the planets in high precision and accuracy and correct them for the orbital motion of the Earth is a primary condition. We present transit timing variations and update the ephemeris information of 5 transiting planets; HAT-P-23b, WASP-103b, GJ-1214b, WASP-69b, and KELT-3b within this contribution, based on all the quality transit light curves from amateur and professional observers, converted to Dynamic Barycentric Julian Days (BJD-TDB).

[47]  arXiv:1911.08338 [pdf, other]

Title: Spectroscopically Identified Cataclysmic Variables from LAMOST survey. I. The Sample

Authors: Wen Hou, A-Li Luo, Yin-Bi Li, Li Qin

Comments: Accepted by AJ, 21 pages, 17 figures

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

A sample of Cataclysmic Variables (CVs) is presented including spectroscopically identified 380 spectra of 245 objects, of which 58 CV candidates are new discoveries. The BaggingTopPush and the Random Forest algorithms are applied to the Fifth Data Release (DR5) of LAMOST to retrieve CVs with strong emission lines and with broad absorption lines respectively. Based on spectroscopic classification, 134 dwarf novae, 41 nova-like variables and 19 magnetic CVs are identified from the sample. In addition, 89 high--inclination systems and 33 CVs showing companion stars are recognized and discussed for their distinct spectral characteristics. Comparisons between CVs from LAMOST and from published catalogs are made in spatial and magnitude distribution, and the difference of their locus in Gaia color--absolute magnitude diagram (CaMD) are also investigated. More interestingly, for two dwarf novae observed through LAMOST and SDSS in different epoch, their spectra both in quiescence phase and during outburst are exhibited.

[48]  arXiv:1911.08353 [pdf, other]

Title: Wide angle effects for peculiar velocities

Authors: Emanuele Castorina, Martin White

Comments: 13 pages, 10 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

The line-of-sight peculiar velocities of galaxies contribute to their observed redshifts, breaking the translational invariance of galaxy clustering down to a rotational invariance around the observer. This becomes important when the line-of-sight direction varies significantly across a survey, leading to what are known as `wide angle' effects in redshift space distortions. Wide-angle effects will also be present in measurements of the momentum field, i.e. the galaxy density-weighted velocity field, in upcoming peculiar velocity surveys. In this work we study how wide-angle effects modify the predicted correlation function and power spectrum for momentum statistics, both in auto-correlation and in cross-correlation with the density field. Using both linear theory and the Zeldovich approximation, we find that deviations from the plane-parallel limit are large and could become important in data analysis for low redshift surveys. We point out that even multipoles in the cross-correlation between density and momentum are non-zero regardless of the choice of line of sight, and therefore contain new cosmological information that could be exploited. We discuss configuration-space, Fourier-space and spherical analyses, providing exact expressions in each case rather than relying on an expansion in small angles. We hope these expressions will be of use in the analysis of upcoming surveys for redshift-space distortions and peculiar velocities.

[49]  arXiv:1911.08357 [pdf, other]

Title: ROME (Radio Observations of Magnetized Exoplanets). II. HD 189733 Does Not Accrete Significant Material from its Exoplanet like a T Tauri Star from A Disk

Authors: Matthew Route (1), Leslie W. Looney (2) ((1) Purdue University, (2) University of Illinois, Urbana-Champaign)

Comments: Accepted by ApJ; 27 pages, 3 tables, 3 figures

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)

It has been asserted that the primary star in the HD 189733 system steadily accretes evaporated exospheric gases from its ``hot Jupiter'' companion, rather like a T Tauri star accreting from a disk. We conduct statistical and periodogram analyses of the photometric time series of the primary, as acquired by the automated photoelectric telescope (APT), Microvariability and Oscillations of Stars (MOST), and Wise Observatory, to investigate this claim with the goal of revealing the presence of accretion shocks or photospheric accretion hotspots as are found in T Tauri systems such as AA Tau. None of the anticipated features were found. We re-analyze existing radio, optical, ultraviolet, and X-ray data within the framework of accreting T Tauri systems to determine physical quantities such as plasma density and temperature, accretion rate, and flare lengths. We find that with an accretion rate of $\dot{M}\sim10^{9}$ to 10$^{11}$ g s$^{-1}$, the star is more similar to a system that intermittently absorbs gas from sungrazing comets in outburst than classical T Tauri systems, which have accretion rates at least two orders of magnitude larger. If such accretion exists, it would result in undetectably low activity at all wavelengths. Alternatively, all of the emission properties observed thus far are in agreement with stellar activity from a magnetically active star.

[50]  arXiv:1911.08387 [pdf, other]

Title: Binary population synthesis models for core-collapse gamma-ray burst progenitors

Authors: A. A. Chrimes, E. R. Stanway, J. J. Eldridge

Comments: Accepted for publication in MNRAS

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)

Long-duration gamma-ray bursts (GRBs) are understood to be the final fate for a subset of massive, stripped envelope, rapidly rotating stars. Beyond this, our knowledge of the progenitor systems is limited. Using the BPASS (Binary Population and Spectral Synthesis) stellar evolution models, we investigate the possibility that some massive stars in binaries can maintain the angular momentum required for jet production, while still loosing their outer envelope through winds or binary interactions. We find that a total hydrogen mass of less than 0.0005 Msun and a helium ejecta mass fraction of less than 0.20 provide the best thresholds for the supernova type II/Ibc and Ib/Ic divisions respectively. Tidal interactions in binaries are accounted for by applying a tidal algorithm to post-process the stellar evolution models output by BPASS. We show that the observed volumetric gamma-ray burst rate evolution can be recreated using two distinct pathways and plausible distributions for burst parameters. In the first pathway, stars are spun up by mass accretion into a quasi-homogeneous state. In the second, tides maintain rotation where otherwise the star would spin down. Both lead to type Ic supernova progenitors, and a metallicity distribution consistent with the GRB host galaxy population. The inferred core angular momentum threshold for jet production is consistent with theoretical requirements for collapsars, given the assumptions made in our model. We can therefore reproduce several aspects of core collapse supernova/GRB observation and theory simultaneously. We discuss the predicted observable properties of GRB progenitors and their surviving companions.

[51]  arXiv:1911.08390 [pdf, other]

Title: Bayesian Characterization of Main Sequence Binaries in the Old Open Cluster NGC 188

Authors: Roger E. Cohen (1), Aaron M. Geller (2 and 3), Ted von Hippel (4) ((1) STScI, (2) CIERA, Northwestern U., (3) Adler Planetarium, (4) ERAU)

Comments: AJ accepted

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)

The binary fractions of open and globular clusters yield powerful constraints on their dynamical state and evolutionary history. We apply publicly available Bayesian analysis code to a $UBVRIJHK_{S}$ photometric catalog of the old open cluster NGC 188 to detect and characterize photometric binaries along the cluster main sequence. This technique has the advantage that it self-consistently handles photometric errors, missing data in various bandpasses, and star-by-star prior constraints on cluster membership. Simulations are used to verify uncertainties and quantify selection biases in our analysis, illustrating that among binaries with mass ratios >0.5, we recover the binary fraction to better than 7% in the mean, with no significant dependence on binary fraction and a mild dependence on assumed mass ratio distribution. Using our photometric catalog, we recover the majority (65%$\pm$11%) of spectroscopically identified main sequence binaries, including 8 of the 9 with spectroscopically measured mass ratios. Accounting for incompleteness and systematics, we derive a mass ratio distribution that rises toward lower mass ratios (within our $q >$0.5 analysis domain). We observe a raw binary fraction for solar-type main sequence stars with mass ratios $q >$0.5 of 42%$\pm$4%, independent of the assumed mass ratio distribution to within its uncertainties, consistent with literature values for old open clusters but significantly higher than the field solar-type binary fraction. We confirm that the binaries identified by our method are more concentrated than single stars, in agreement with previous studies, and we demonstrate that the binary nature of those candidates which remain unidentified spectroscopically is strongly supported by photometry from Gaia DR2.

[52]  arXiv:1911.08391 [pdf, other]

Title: The impact of atmospheric dispersion in the performance of high-resolution spectrographs

Authors: Bachar Wehbe, Alexandre Cabral, Jorge Martins, Pedro Figueira, Nuno Santos, Gerardo Ávila

Comments: accepted for publications in MNRAS

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM)

Differential atmospheric dispersion is a wavelength-dependent effect introduced by the atmosphere. It is one of the instrumental errors that can affect the position of the target as perceived on the sky and its flux distribution. This effect will affect the results of astronomical observations if not corrected by an atmospheric dispersion corrector (ADC). In high-resolution spectrographs, in order to reach a radial velocity (RV) precision of 10 cm/s, an ADC is expected to return residuals at only a few tens of milli-arcseconds (mas). In fact, current state-of-the-art spectrographs conservatively require this level of residuals, although no work has been done to quantify the impact of atmospheric dispersion. In this work we test the effect of atmospheric dispersion on astronomical observations in general, and in particular on RV precision degradation and flux losses. Our scientific objective was to quantify the amount of residuals needed to fulfill the requirements set on an ADC during the design phase. We found that up to a dispersion of 100 mas, the effect on the RV is negligible. However, on the flux losses, such a dispersion can create a loss of ~2% at 380 nm, a significant value when efficiency is critical. The requirements set on ADC residuals should take into consideration the atmospheric conditions where the ADC will function, and also all the aspects related with not only the RV precision requirements but also the guiding camera used, the tolerances on the flux loss, and the different melt data of the chosen glasses.

[53]  arXiv:1911.08407 [pdf, ps, other]

Title: Bulk viscosity in neutron stars with hyperon cores

Authors: D. D. Ofengeim (1), M. E. Gusakov (1), P. Haensel (2), M. Fortin (2) ((1) Ioffe Institute, St. Petersburg, Russia, (2) N. Copernicus Astronomical Center, Warszawa, Poland)

Comments: 21 pages, 13 figures, 4 tables, accepted in PRD (selected as PRD editors' suggestion)

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

It is well-known that r-mode oscillations of rotating neutron stars may be unstable with respect to the gravitational wave emission. It is highly unlikely to observe a neutron star with the parameters within the instability window, a domain where this instability is not suppressed. But if one adopts the `minimal' (nucleonic) composition of the stellar interior, a lot of observed stars appear to be within the r-mode instability window. One of the possible solutions to this problem is to account for hyperons in the neutron star core. The presence of hyperons allows for a set of powerful (lepton-free) non-equilibrium weak processes, which increase the bulk viscosity, and thus suppress the r-mode instability. Existing calculations of the instability windows for hyperon NSs generally use reaction rates calculated for the $\Sigma^-\Lambda$ hyperonic composition via the contact $W$ boson exchange interaction. In contrast, here we employ hyperonic equations of state where the $\Lambda$ and $\Xi^-$ are the first hyperons to appear (the $\Sigma^-$'s, if they are present, appear at much larger densities), and consider the meson exchange channel, which is more effective for the lepton-free weak processes. We calculate the bulk viscosity for the non-paired $npe\mu\Lambda\Xi^-$ matter using the meson exchange weak interaction. A number of viscosity-generating non-equilibrium processes is considered (some of them for the first time in the neutron-star context). The calculated reaction rates and bulk viscosity are approximated by simple analytic formulas, easy-to-use in applications. Applying our results to calculation of the instability window, we argue that accounting for hyperons may be a viable solution to the r-mode problem.

[54]  arXiv:1911.08431 [pdf, other]

Title: Obliquity Evolution of Circumstellar Planets in Sun-like Stellar Binaries

Authors: Billy Quarles, Gongjie Li, Jack J. Lissauer

Comments: 19 pages, 14 figures, 2 tables; Published in ApJ

Journal-ref: ApJ 886 56 (2019)

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

Changes in planetary obliquity, or axial tilt, influence the climates on Earth-like planets. In the solar system, the Earth's obliquity is stabilized due to interactions with our moon and the resulting {small amplitude variations ($\sim$2.4\degree)} are beneficial for advanced life. Most Sun-like stars have at least one stellar companion and the habitability of circumstellar exoplanets is shaped by their stellar companion. We show that a stellar companion can dramatically change whether {Earth-like obliquity stability is} possible through planetary orbital precession relative to the binary orbit or resonant pumping of the obliquity through spin-orbit interactions. We present a new formalism for the planetary spin precession that accounts for orbital misalignments between the planet and binary. Using numerical modeling in $\alpha$ Centauri AB we show: a stark contrast between the planetary obliquity variations depending on the host star, planetary neighbors limit the possible spin states for {Earth-like obliquity stability}, and the presence of a moon can destabilize the obliquity, defying our Earth-based expectations. An Earth-like rotator orbiting the primary star would experience {small} obliquity variations for 87\%, 74\%, or 54\% of Solar type binaries, depending on the mass of the primary (0.8, 1.0, or 1.2 M$_\odot$, respectively). Thus, Earth-like planets likely experience much larger obliquity variations, with more extreme climates, unless they are in specific states, such as orbiting nearly planar with the binary and rotating retrograde (backwards) like Venus.

[55]  arXiv:1911.08436 [pdf, other]

Title: High-resolution spectropolarimetric observations of the temporal evolution of magnetic fields in photospheric bright points

Authors: Peter H. Keys, Aaron Reid, Mihalis Mathioudakis, Sergiy Shelyag, Vasco M. J. Henriques, Rebecca L. Hewitt, Dario Del Moro, Shahin Jafarzadeh, David B. Jess, Marco Stangalini

Comments: Accepted for publication in A&A, 15 pages, 10 figures

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

Context. Magnetic bright points (MBPs) are dynamic, small-scale magnetic elements often found with field strengths of the order of a kilogauss within intergranular lanes in the photosphere. Aims. Here we study the evolution of various physical properties inferred from inverting high-resolution full Stokes spectropolarimetry data obtained from ground-based observations of the quiet Sun at disc centre. Methods. Using automated feature-tracking algorithms, we studied 300 MBPs and analysed their temporal evolution as they evolved to kilogauss field strengths. These properties were inferred using both the NICOLE and SIR Stokes inversion codes. We employ similar techniques to study radiative magnetohydrodynamical simulations for comparison with our observations. Results. Evidence was found for fast (~30 - 100s) amplification of magnetic field strength (by a factor of 2 on average) in MBPs during their evolution in our observations. Similar evidence for the amplification of fields is seen in our simulated data. Conclusions. Several reasons for the amplifications were established, namely, strong downflows preceding the amplification (convective collapse), compression due to granular expansion and mergers with neighbouring MBPs. Similar amplification of the fields and interpretations were found in our simulations, as well as amplification due to vorticity. Such a fast amplification will have implications for a wide array of topics related to small-scale fields in the lower atmosphere, particularly with regard to propagating wave phenomena in MBPs.

[56]  arXiv:1911.08450 [pdf, other]

Title: Chemical evolution of ultra-faint dwarf galaxies: testing the IGIMF

Authors: E. Lacchin, F. Matteucci, F. Vincenzo, M. Palla

Subjects: Astrophysics of Galaxies (astro-ph.GA)

We test the integrated galactic initial mass function (IGIMF) on the chemical evolution of 16 ultra-faint dwarf (UFD) galaxies discussing in detail the results obtained for three of them: Bo\"otes I, Bo\"otes II and Canes Venatici I, taken as prototypes of the smallest and the largest UFDs. These objects have very small stellar masses ($\sim 10^3-10^4 \mathrm{M_{\odot}}$) and quite low metallicities ([Fe/H]$<-1.0$ dex). We consider three observational constraints: the present-day stellar mass, the [$\alpha$/Fe] vs. [Fe/H] relation and the stellar metallicity distribution function. Our model follows in detail the evolution of several chemical species (H, He, $\alpha$-elements and Fe). We take into account detailed nucleosynthesis and gas flows (in and out). Our results show that the IGIMF, coupled with the very low star formation rate predicted by the model for these galaxies ($\sim 10^{-4}-10^{-6}\ \mathrm{M_{\odot}yr^{-1}}$), cannot reproduce the main chemical properties, because it implies a negligible number of core-collapse SNe and even Type Ia SNe, the most important polluters of galaxies. On the other hand, a constant classical Salpeter IMF gives the best agreement with data. We suggest for all the UFDs studied a very short infall time-scale and high galactic wind efficiencies. Comparing with Galaxy data we suggest that UFDs could not be the building blocks of the entire Galactic halo, although more data are necessary to draw firmer conclusions.

[57]  arXiv:1911.08462 [pdf, other]

Title: Metis: the Solar Orbiter visible light and ultraviolet coronal imager

Authors: Ester Antonucci, Marco Romoli, Vincenzo Andretta, Silvano Fineschi, Petr Heinzel, J. Daniel Moses, Giampiero Naletto, Gianalfredo Nicolini, Daniele Spadaro, Luca Teriaca, Arkadiusz Berlicki, Gerardo Capobianco, Giuseppe Crescenzio, Vania Da Deppo, Mauro Focardi, Fabio Frassetto, Klaus Heerlein, Federico Landini, Enrico Magli, Andrea Marco Malvezzi, Giuseppe Massone, Radek Melich, Piergiorgio Nicolosi, Giancarlo Noci, Maurizio Pancrazzi, Maria G. Pelizzo, Luca Poletto, Clementina Sasso, Udo Schühle, Sami K. Solanki, Leonard Strachan, Roberto Susino, Giuseppe Tondello, Michela Uslenghi, Joachim Woch, Lucia Abbo, Alessandro Bemporad, Marta Casti, Sergio Dolei, Catia Grimani, Mauro Messerotti, Marco Ricci, Thomas Straus, Daniele Telloni, Paola Zuppella, Frederic Auchère, Roberto Bruno, et al. (56 additional authors not shown)

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Metis is the first solar coronagraph designed for a space mission capable of performing simultaneous imaging of the off-limb solar corona in both visible and UV light. The observations obtained with Metis aboard the Solar Orbiter ESA-NASA observatory will enable us to diagnose, with unprecedented temporal coverage and spatial resolution, the structures and dynamics of the full corona from 1.7 $R_\odot$ to about 9 $R_\odot$. Due to the uniqueness of the Solar Orbiter mission profile, Metis will be able to observe the solar corona from a close vantage point (down to 0.28 AU), achieving out-of-ecliptic views with the increase of the orbit inclination over time. Moreover, observations near perihelion, during the phase of lower rotational velocity of the solar surface relative to the spacecraft, will allow longer-term studies of the coronal features. Thanks to a novel occultation design and a combination of a UV interference coating of the mirrors and a spectral bandpass filter, Metis images the solar corona simultaneously in the visible light band, between 580 and 640 nm, and in the UV H I Lyman-{\alpha} line at 121.6 nm. The coronal images in both the UV Lyman-{\alpha} and polarised visible light are obtained at high spatial resolution with a spatial scale down to about 2000 km and 15000 km at perihelion, in the cases of the visible and UV light, respectively. A temporal resolution down to 1 second can be achieved when observing coronal fluctuations in visible light. The Metis measurements will allow for complete characterisation of the main physical parameters and dynamics of the electron and neutral hydrogen/proton plasma components of the corona in the region where the solar wind undergoes acceleration and where the onset and initial propagation of coronal mass ejections take place, thus significantly improving our understanding of the region connecting the Sun to the heliosphere.

[58]  arXiv:1911.08471 [pdf, other]

Title: Modelling the large scale structure of the Universe as a function of cosmology and baryonic physics

Authors: Giovanni Aricò, Raul E. Angulo, Carlos Hernández-Monteagudo, Sergio Contreras, Matteo Zennaro, Marcos Pellejero-Ibañez, Yetli Rosas-Guevara

Comments: 23 pages, 15 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)

We present and test a framework that models the three-dimensional distribution of mass in the Universe as a function of cosmological and astrophysical parameters. Our approach combines two different techniques: a rescaling algorithm that modifies the cosmology of gravity-only N-body simulations, and a baryonification algorithm which mimics the effects of astrophysical processes induced by baryons, such as star formation and AGN feedback. We show how this approach can accurately reproduce the effects of baryons on the matter power spectrum of various state-of-the-art hydro-dynamical simulations (EAGLE, Illustris, Illustris-TNG, Horizon-AGN, and OWLS,Cosmo-OWLS and BAHAMAS), to percent level from very large down to small, highly nonlinear scales, k= 5 h/Mpc, and from z=0 up to z=2. We highlight that, thanks to the heavy optimisation of the algorithms, we can obtain these predictions for arbitrary baryonic models and cosmology (including massive neutrinos and dynamical dark energy models) with an almost negligible CPU cost. Therefore, this approach is efficient enough for cosmological data analyses. With these tools in hand we explore the degeneracies between cosmological and astrophysical parameters in the nonlinear mass power spectrum. Our findings suggest that after marginalising over baryonic physics, cosmological constraints inferred from weak gravitational lensing should be moderately degraded.

[59]  arXiv:1911.08475 [pdf, other]

Title: The Gravitational Lensing Signatures of BOSS Voids in the Cosmic Microwave Background

Authors: Srinivasan Raghunathan, Seshadri Nadathur, Blake D. Sherwin, Nathan Whitehorn

Comments: 19 pages, 8 figures, 3 tables; to be submitted to ApJ; comments welcome

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We report a $5.3\sigma$ detection of the gravitational lensing effect of cosmic voids from the Baryon Oscillation Spectroscopic (BOSS) Data Release 12 seen in the $Planck$ 2018 cosmic microwave background (CMB) lensing convergence map. To make this detection, we introduce new optimal techniques for void stacking and filtering of the CMB maps, such as binning voids by a combination of their observed galaxy density and size to separate those with distinctive lensing signatures. We calibrate theoretical expectations for the void-lensing signal using mock catalogs generated in a suite of 108 full-sky lensing simulations from Takahashi et al. (2017). Relative to these templates, we measure the lensing amplitude parameter in the data to be $A_L=1.10 \pm 0.21$ using a matched-filter stacking technique, and confirm it using an alternative Wiener filtering method. We demonstrate that the result is robust against thermal Sunyaev-Zel'dovich contamination and other sources of systematics. We use the lensing measurements to test the relationship between the matter and galaxy distributions within voids, and show that the assumption of linear bias with a value consistent with galaxy clustering results is discrepant with observation at $\sim 3\sigma$; we explain why such a result is consistent with simulations and previous results, and is expected as a consequence of void selection effects. We forecast the potential for void-CMB lensing measurements in future data from the Advanced ACT, Simons Observatory and CMB-S4 experiments, showing that, for the same number of voids, the achievable precision improves by a factor of more than two compared to $Planck$.

Cross-lists for Wed, 20 Nov 19

[60]  arXiv:1911.06099 (cross-list from hep-ph) [pdf, ps, other]

Title: Mass varying neutrinos with different quintessence potentials

Authors: Sayan Mandal, Gennady Y. Chitov, Olga Avsajanishvili, Bijit Singha, Tina Kahniashvili

Comments: 16 pages, 18 figures. Comments welcome

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)

The mass-varying neutrino scenario is analyzed for three trial quintessence potentials (Ferreira-Joyce, inverse exponential, and thawing oscillating). The neutrino mass is generated via Yukawa coupling to the scalar field which represents dark energy. The inverse exponential and oscillating potentials are shown to successfully generate the neutrino masses in the range $m \sim 10^{-2}-10^{-3}~$eV and to yield the current dark energy density in the regime of the late-time acceleration of the Universe. Depending on the choice of potentials, the acceleration could occur in two different regimes: (1) the regime of instability, and (2) the stable regime. The first regime of instability is after the Universe underwent a first-order transition and is rolling toward the new stable vacuum. The imaginary sound velocity $c^2_s < 0$ in this regime implies growing fluctuations of the neutrino density (clustering). In the second regime, the Universe smoothly changes its stable states via a continuous transition. Since $c^2_s > 0$, the neutrino density is stable. For all cases the predicted late-time acceleration of the Universe is asymptotically very close to that of the $\Lambda$CDM model. Further extensions of the theory to modify the neutrino sector of the Standard Model and to incorporate inflation are also discussed.

[61]  arXiv:1911.06714 (cross-list from cs.DC) [pdf, other]

Title: Two-level Dynamic Load Balancing for High Performance Scientific Applications

Authors: Ali Mohammed, Aurelien Cavelan, Florina M. Ciorba, Ruben M. Cabezon, Ioana Banicesu

Subjects: Distributed, Parallel, and Cluster Computing (cs.DC); Instrumentation and Methods for Astrophysics (astro-ph.IM); Performance (cs.PF); Computational Physics (physics.comp-ph)

Scientific applications are often complex, irregular, and computationally-intensive. To accommodate the ever-increasing computational demands of scientific applications, high-performance computing (HPC) systems have become larger and more complex, offering parallelism at multiple levels (e.g., nodes, cores per node, threads per core). Scientific applications need to exploit all the available multilevel hardware parallelism to harness the available computational power. The performance of applications executing on such HPC systems may adversely be affected by load imbalance at multiple levels, caused by problem, algorithmic, and systemic characteristics. Nevertheless, most existing load balancing methods do not simultaneously address load imbalance at multiple levels. This work investigates the impact of load imbalance on the performance of three scientific applications at the thread and process levels. We jointly apply and evaluate selected dynamic loop self-scheduling (DLS) techniques to both levels. Specifically, we employ the extended LaPeSD OpenMP runtime library at the thread level and extend the DLS4LB MPI-based dynamic load balancing library at the process level. This approach is generic and applicable to any multiprocess-multithreaded computationally-intensive application (programmed using MPI and OpenMP). We conduct an exhaustive set of experiments to assess and compare six DLS techniques at the thread level and eleven at the process level. The results show that improved application performance, by up to 21%, can only be achieved by jointly addressing load imbalance at the two levels. We offer insights into the performance of the selected DLS techniques and discuss the interplay of load balancing at the thread level and process level.

[62]  arXiv:1911.07838 (cross-list from hep-ph) [pdf, other]

Title: Dynamical evolution of axion condensates under stimulated decays into photons

Authors: Pierluca Carenza (Bari U. & INFN Bari), Alessandro Mirizzi (Bari U. & INFN Bari), Günter Sigl (II Inst. Theor. Phys., Hamburg U.)

Comments: 15 pages, 3 pdf figures

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

Dark matter axion condensates may experience stimulated decays into photon pairs. This effect has been often interpreted as a parametric resonance of photons from the axion-photon coupling, leading to an exponential growth of the photon occupation number in a narrow instability band. Most of the previous literature does not consider the possible evolution of the axion field due to the photon growth. We revisit this effect presenting a mean field solution of the axion-photon kinetic equations, in terms of number of photons and pair correlations. We study the limit of no axion depletion, recovering the known instability. Moreover, we extend the results including a possible depletion of the axion field. In this case we find that the axion condensate exhibits the behaviour of an inverted pendulum. We discuss the relevance of these effects for two different cases: an homogeneous axion field at recombination and a localized axion clump and discuss constraints that could result from the induced photon background.

[63]  arXiv:1911.07862 (cross-list from hep-ph) [pdf, other]

Title: Superradiance and the Spins of Black Holes from LIGO and X-ray binaries

Authors: Nicolas Fernandez, Akshay Ghalsasi, Stefano Profumo

Comments: 10 pages, 5 Figures, comments welcome

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)

Measurements of the spin of stellar mass black holes (BHs) are now possible both through LIGO observations of binary BH mergers and for BHs in X-ray binary systems. The spins of BHs as inferred from LIGO observations suggest that BH spins are on the lower end of what is expected for a ``flat'' distribution of spins, while those from BHs in X-ray binaries tend to be large. Superradiance, a process that can effectively reduce the spin of BHs before they merge, could explain the lower observed spins in binary BH mergers for a non self-interacting light boson. In this paper, we use Bayesian analysis to infer the posterior probability distribution for the mass of a light boson that could fit LIGO data. We also analyze spins of BHs from X-ray binaries, and find that the X-ray binary data can be explained by superradiance due to a light boson with large self-interactions. We infer the mass range for such a boson that is consistent with the X-ray binary data.

[64]  arXiv:1911.07867 (cross-list from hep-ph) [pdf, other]

Title: Light Dark Matter and Superfluid He-4 from EFT

Authors: Andrea Caputo, Angelo Esposito, Antonio D. Polosa

Comments: Talk presented at the TAUP 2019 conference; 4 pages, 2 figures

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

We study the response of a He-4 detector to the interaction of sub-GeV dark matter using an effective field theory for the superfluid. We compute the lifetime of the phonon, which agrees with what known from standard techniques, hence providing an important check of the effective field theory. We then study the process of emission of two phonons, and show how its rate is much more suppressed than the phase space expectations; this is a consequence of the conservation of the current associated to the superfluid symmetries.

[65]  arXiv:1911.07885 (cross-list from hep-ph) [pdf, other]

Title: On the Wondrous Stability of ALP Dark Matter

Authors: Gonzalo Alonso-Álvarez, Rick S. Gupta, Joerg Jaeckel, Michael Spannowsky

Comments: 20 pages, 3 figures

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

The very low mass and small coupling of axion-like particles (ALPs) is usually taken as a guarantor of their cosmological longevity, making them excellent dark matter candidates. That said, Bose enhancement could stimulate decays and challenge this paradigm. Here, we analyze and review the cosmological decay of ALPs into photons, taking Bose enhancement into account, thereby going beyond the usual naive perturbative estimate. At first glance, this calculation seems to yield an exponentially growing resonance and therefore an extremely fast decay rate. However, the redshifting of the decay products due to the expansion of the Universe as well as the effective plasma mass of the photon can prevent an efficient resonance. While this result agrees with existing analyses of the QCD axion, for more general ALPs that can feature an enhanced photon coupling, stability is only ensured by a combination of the expansion and the plasma effects.

[66]  arXiv:1911.08086 (cross-list from physics.plasm-ph) [pdf, other]

Title: Energy Dissipation and Entropy in Collisionless Plasma

Authors: Senbei Du, Gary P. Zank, Fan Guo, Xiaocan Li

Comments: 19 pages, 4 figure

Subjects: Plasma Physics (physics.plasm-ph); Solar and Stellar Astrophysics (astro-ph.SR); Space Physics (physics.space-ph)

It is well known that collisionless systems are dissipation free from the perspective of particle collision and thus conserve entropy. On the other hand, processes such as magnetic reconnection and turbulence appear to convert large-scale magnetic energy into heat. In this paper, we investigate the energization and heating of collisionless plasma. The dissipation process is discussed in terms of fluid entropy in both isotropic and gyrotropic forms. Evolution equations for the entropy are derived and they reveal mechanisms that lead to changes in fluid entropy. These equations are verified by a collisionless particle-in-cell simulation of multiple reconnecting current sheets. In addition to previous findings regarding the pressure tensor, we emphasize the role of heat flux in the dissipation process.

[67]  arXiv:1911.08092 (cross-list from q-bio.PE) [pdf, ps, other]

Title: Emergence of life in an inflationary universe

Authors: Tomonori Totani

Comments: 11 pages, 1 figure

Subjects: Populations and Evolution (q-bio.PE); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Earth and Planetary Astrophysics (astro-ph.EP); Biomolecules (q-bio.BM)

Abiotic emergence of ordered information stored in the form of RNA is an important unresolved problem concerning the origin of life. A polymer longer than 40--100 nucleotides is necessary to expect a self-replicating activity, but the formation of such a long polymer having a correct nucleotide sequence by random reactions seems statistically unlikely. However, our universe, created by a single inflation event, likely includes more than $10^{100}$ Sun-like stars. If life can emerge at least once in such a large volume, it is not in contradiction with our observations of life on Earth, even if the expected number of abiogenesis events is negligibly small within the observable universe that contains only $10^{22}$ stars. Here, a quantitative relation is derived between the minimum RNA length $l_{\min}$ required to be the first biological polymer, and the universe size necessary to expect the formation of such a long and active RNA by randomly adding monomers. It is then shown that an active RNA can indeed be produced somewhere in an inflationary universe. On the other hand, $l_{\min}$ must be shorter than $\sim$20 nucleotides for the abiogenesis probability close to unity on a terrestrial planet, but a self-replicating activity is not expected for such a short RNA. Therefore, if extraterrestrial organisms of a different origin from those on Earth are discovered in the future, it would imply an unknown mechanism at work to polymerize nucleotides much faster than random statistical processes.

[68]  arXiv:1911.08268 (cross-list from gr-qc) [pdf, other]

Title: Pattern of lensed chirp gravitational wave signal and its implication on the mass and position of lens

Authors: Dongze Sun, Xilong Fan

Comments: undergrad project. comments are welcome

Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE)

We prose a new measurement strategy of the estimation of the lens mass, as well as the actual amplification, of the lens through the modulation patten of lensed gravitational wave signals alone. This can be done by measuring the frequency and amplitude ratio of peaks and valleys of the modulation pattern of CBC signals, known as "beat", which is a time domain phenomenon of strong lens effect.

[69]  arXiv:1911.08317 (cross-list from hep-ph) [pdf, ps, other]

Title: Spin effects in neutrino gravitational scattering

Authors: Maxim Dvornikov (IZMIRAN)

Comments: 16 pages in LaTeX2e, 20 eps figures

Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)

We study spin oscillations of neutrinos gravitationally scattered off a nonrotating black hole (BH). We derive the transition and survival probabilities of spin oscillations in quadratures when neutrinos interacts with BH only. The dependence of the probabilities on the impact parameter is analyzed. Then, we obtain the effective Schr\"{o}dinger equation for neutrino spin oscillations in neutrino scattering off BH surrounded by background matter. This equation is solved numerically in the case of a supermassive BH with a realistic accretion disk. We find that the observed neutrino fluxes can be reduced almost 20% because of spin oscillations when neutrinos experience gravitational scattering. The neutrino interaction with an accretion disk results in the additional asymmetry in the intensities of outgoing fluxes depending on the neutrino trajectory.

[70]  arXiv:1911.08327 (cross-list from cs.LG) [pdf, other]

Title: Eliminating artefacts in Polarimetric Images using Deep Learning

Authors: Dhruv Paranjpye, Ashish Mahabal, A.N. Ramaprakash, Gina Panopoulou, Kieran Cleary, Anthony Readhead, Dmitry Blinov, Kostas Tassis

Comments: 7 pages, 15 figures

Subjects: Machine Learning (cs.LG); Instrumentation and Methods for Astrophysics (astro-ph.IM); Machine Learning (stat.ML)

Polarization measurements done using Imaging Polarimeters such as the Robotic Polarimeter are very sensitive to the presence of artefacts in images. Artefacts can range from internal reflections in a telescope to satellite trails that could contaminate an area of interest in the image. With the advent of wide-field polarimetry surveys, it is imperative to develop methods that automatically flag artefacts in images. In this paper, we implement a Convolutional Neural Network to identify the most dominant artefacts in the images. We find that our model can successfully classify sources with 98\% true positive and 97\% true negative rates. Such models, combined with transfer learning, will give us a running start in artefact elimination for near-future surveys like WALOP.

[71]  arXiv:1911.08371 (cross-list from gr-qc) [pdf, ps, other]

Title: No nonminimally coupled massless scalar hair for spherically symmetric neutral black holes

Authors: Shahar Hod

Comments: 8 pages

Journal-ref: Physics Letters B 771, 521 (2017)

Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)

We provide a remarkably compact proof that spherically symmetric neutral black holes cannot support static nonminimally coupled massless scalar fields. The theorem is based on causality restrictions imposed on the energy-momentum tensor of the fields near the regular black-hole horizon.

[72]  arXiv:1911.08472 (cross-list from hep-ph) [pdf, other]

Title: Axion Fragmentation

Authors: Nayara Fonseca, Enrico Morgante, Ryosuke Sato, Géraldine Servant

Comments: 28 pages and 17 figures in main text, 23 pages and 7 figures in appendices

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Theory (hep-th)

We investigate the production of axion quanta during the early universe evolution of an axion-like field rolling down a wiggly potential. We compute the growth of quantum fluctuations and their back-reaction on the homogeneous zero-mode. We evaluate the transfer of kinetic energy from the zero mode to the quantum fluctuations and the conditions to decelerate the axion zero-mode as a function of the Hubble rate, the slope of the potential, the size of the barriers and the initial field velocity. We discuss how these effects impact the relaxion mechanism.

[73]  arXiv:1911.08473 (cross-list from hep-ph) [pdf, other]

Title: Relaxion Fluctuations (Self-stopping Relaxion) and Overview of Relaxion Stopping Mechanisms

Authors: Nayara Fonseca, Enrico Morgante, Ryosuke Sato, Géraldine Servant

Comments: 39 pages and 9 figures in main text, and 29 pages and 32 figures in appendices

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

In implementations of the electroweak scale cosmological relaxation mechanism proposed so far, the effect of the quantum fluctuations of the homogeneous relaxion field has been ignored. We show that they can grow during the classical cosmological evolution of the relaxion field passing through its many potential barriers. The resulting production of relaxion particles can act as an efficient stopping mechanism for the relaxion. We revisit the original relaxion proposal and determine under which conditions inflation may no longer be needed as a source of friction. We review alternative stopping mechanisms and determine in detail the allowed parameter space for each of them (whether happening before, during and after inflation), also considering and severely constraining the case of friction from electroweak gauge boson production in models with large and Higgs-independent barriers.

Replacements for Wed, 20 Nov 19

[74]  arXiv:1712.06072 (replaced) [pdf, other]

Title: Exploring the CPT violation and birefringence of gravitational waves with ground- and space-based gravitational-wave interferometers

Authors: Sai Wang

Comments: Preprint, 16 pages, 1 figure, 1 table, 2 appendices. All comments are welcome

Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE)

[75]  arXiv:1812.11088 (replaced) [pdf, other]

Title: M subdwarf research. I. Identification, modified classification system, and sample construction

Authors: Shuo Zhang, A-Li Luo, Georges Comte, John E. Gizis, Rui Wang, Yinbi Li, Li Qin, Xiao Kong, Yu Bai, Zhenping Yi

Comments: 22 pages, 10 figures, published in ApJS(2019, ApJS, 240, 31) updated with the erratum in ApJS(2019, ApJS, 243, 37)

Journal-ref: 2019ApJS..240...31Z 2019ApJS..243...37Z

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

[76]  arXiv:1901.07640 (replaced) [pdf, other]

Title: Stability of the co-orbital resonance under dissipation: Application to its evolution in protoplanetary discs

Authors: Adrien Leleu, Gavin Coleman, Sareh Ataiee

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

[77]  arXiv:1901.11182 (replaced) [pdf, other]

Title: Resolving 3D Disk Orientation using High-Resolution Images: New Constraints on Circumgalactic Gas Inflows

Authors: Stephanie H. Ho, Crystal L. Martin

Comments: 15 pages with 8 figures and 2 tables; accepted for publication in ApJ

Subjects: Astrophysics of Galaxies (astro-ph.GA)

[78]  arXiv:1903.02420 (replaced) [pdf, ps, other]

Title: Detection of Ultra-High Energy neutrinos skimming the Earth due to decay of superheavy dark matter at JEM-EUSO

Authors: Ye Xu

Comments: 8 pages, 4 figures. arXiv admin note: text overlap with arXiv:1804.10719

Journal-ref: Physics of the Dark Universe, 24(2019)100299

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[79]  arXiv:1903.07046 (replaced) [pdf, other]

Title: Cross-correlation of POLARBEAR CMB Polarization Lensing with High-$z$ Sub-mm Herschel-ATLAS galaxies

Authors: M. Aguilar Faundez, K. Arnold, C. Baccigalupi, D. Barron, D. Beck, F. Bianchini, D. Boettger, J. Borrill, J. Carron, K. Cheung, Y. Chinone, H. El Bouhargani, T. Elleflot, J. Errard, G. Fabbian, C. Feng, N. Galitzki, N. Goeckner-Wald, M. Hasegawa, M. Hazumi, L. Howe, D. Kaneko, N. Katayama, B. Keating, N. Krachmalnicoff, A. Kusaka, A. T. Lee, D. Leon, E. Linder, L. N. Lowry, F. Matsuda, Y. Minami, M. Navaroli, H. Nishino, A. T. P. Pham, D. Poletti, G. Puglisi, C. L. Reichardt, B. D. Sherwin, M. Silva-Feaver, R. Stompor, A. Suzuki, O. Tajima, S. Takakura, S. Takatori, G. P. Teply, C. Tsai, C. Verges

Comments: 14 pages, 6 figures, updated to match published version on ApJ

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)

[80]  arXiv:1903.08813 (replaced) [pdf, other]

Title: Stellar mass as a galaxy cluster mass proxy: application to the Dark Energy Survey redMaPPer clusters

Authors: A. Palmese, J. Annis, J. Burgad, A. Farahi, M. Soares-Santos, B. Welch, M. da Silva Pereira, H. Lin, S. Bhargava, D. L. Hollowood, R. Wilkinson, P. Giles, T. Jeltema, A. K. Romer, A. E. Evrard, M. Hilton, C. Vergara Cervantes, A. Bermeo, J. Mayers, J. DeRose, D. Gruen, W. G. Hartley, O. Lahav, B. Leistedt, T. McClintock, E. Rozo, E. S. Rykoff, T. N. Varga, R. H. Wechsler, Y. Zhang, S. Avila, D. Brooks, E. Buckley-Geer, D. L. Burke, A. Carnero Rosell, M. Carrasco Kind, J. Carretero, F. J. Castander, C. Collins, L. N. da Costa, S. Desai, J. De Vicente, H. T. Diehl, J. P. Dietrich, P. Doel, B. Flaugher, P. Fosalba, J. Frieman, J. Garcia-Bellido, D. W. Gerdes, R. A. Gruendl, J. Gschwend, G. Gutierrez, K. Honscheid, D. J. James, E. Krause, K. Kuehn, N. Kuropatkin, A. Liddle, M. Lima, M. A. G. Maia, et al. (24 additional authors not shown)

Comments: 14 pages, 7 figures, addressing MNRAS referee comments

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

[81]  arXiv:1903.10725 (replaced) [pdf, other]

Title: Partial invariants, large-scale dynamo action, and the inverse transfer of magnetic helicity

Authors: Nicholas Rathmann, Peter Ditlevsen

Comments: 16 pages, 6 figures

Subjects: Fluid Dynamics (physics.flu-dyn); High Energy Astrophysical Phenomena (astro-ph.HE); Plasma Physics (physics.plasm-ph); Space Physics (physics.space-ph)

[82]  arXiv:1904.10979 (replaced) [pdf, other]

Title: Stochastic eternal inflation is in the swampland

Authors: Suddhasattwa Brahma, Sarah Shandera

Comments: 5 pages, comments welcome; v2: matches published version

Journal-ref: JHEP 11 (2019) 016

Subjects: High Energy Physics - Theory (hep-th); Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)

[83]  arXiv:1904.11014 (replaced) [pdf, other]

Title: The Nature of Ionized Gas in the Milky Way Galactic Fountain

Authors: Jessica K. Werk, Kate H. R. Rubin, Hannah V. Bish, J. X. Prochaska, Yong Zheng, John M. O'Meara, Daniel Lenz, Cameron Hummels, Alis J. Deason

Comments: 12 figures, 4 tables, Accepted to ApJ. Revision features areal mass accretion rate calculation

Subjects: Astrophysics of Galaxies (astro-ph.GA)

[84]  arXiv:1905.06423 (replaced) [pdf, other]

Title: All at once: transient pulsations, spin down and a glitch from the Pulsating Ultraluminous X-ray Source M82 X-2

Authors: Matteo Bachetti, Thomas J. Maccarone, Murray Brightman, McKinley C. Brumback, Felix Fürst, Fiona A. Harrison, Marianne Heida, Gian Luca Israel, Matthew J. Middleton, John A. Tomsick, Natalie A. Webb, Dominic J. Walton

Comments: 15 pages, 7 figures, 5 tables. Revised version

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[85]  arXiv:1905.09689 (replaced) [pdf, ps, other]

Title: An estimate of the dark matter density from galaxy clusters and supernovae data

Authors: R. F. L. Holanda, R. S. Gonçalves, J. E. Gonzales, J. S. Alcaniz

Comments: JCAP Accepted, 7 pages, 4 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)

[86]  arXiv:1906.07399 (replaced) [pdf, ps, other]

Title: Constraining the Fraction of Core-Collapse Supernovae Harboring Choked Jets with High-energy Neutrinos

Authors: Dafne Guetta, Roi Rahin, Imre Bartos, Massimo Della Valle

Comments: 5 pages, accepted for publication in MNRAS

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[87]  arXiv:1906.09733 (replaced) [pdf, other]

Title: Neutrino currents in wakes of cosmic strings

Authors: Sovan Sau, Soma Sanyal

Comments: 16 pages 2 figure Substantially revised to include estimation of the magnetic field generated in the cosmic string wake

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)

[88]  arXiv:1907.06866 (replaced) [pdf, ps, other]

Title: Probing antigravitational effects through CP violation on the Moon

Authors: G. M. Piacentino, A. Gioiosa, D. Hajdukovicz, A. Palladino, V. Testa, G. Venanzoni

Comments: arXiv admin note: text overlap with arXiv:gr-qc/9906012 by other authors

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Experiment (hep-ex)

[89]  arXiv:1907.11251 (replaced) [pdf, other]

Title: Combined Effects of Rotation and Age Spreads on Extended Main Sequence Turn Offs

Authors: Seth Gossage, Charlie Conroy, Aaron Dotter, Ivan Cabrera-Ziri, Andrew E. Dolphin, Nate Bastian, Julianne J. Dalcanton, Paul Goudfrooij, L. Clifton Johnson, Benjamin F. Williams, Philip Rosenfield, Jason Kalirai, Morgan Fouesneau

Comments: 17 pages, 11 figures

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)

[90]  arXiv:1908.04624 (replaced) [pdf, other]

Title: Non-Equilibrium Spectrum Formation Affecting Solar Irradiance

Authors: Robert J. Rutten

Comments: Accepted for Solar Physics as Editor's Choice lead article of the Topical Selection on irradiance. The arXiv pdf is better for e-reading because the publisher destroyed the citation links and refused correction

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

[91]  arXiv:1908.04773 (replaced) [pdf, other]

Title: Properties of Radial Velocities measurement based on LAMOST-II Medium-Resolution Spectroscopic Observations

Authors: R. Wang, A.-L. Luo, J.-J. Chen, Z.-R.Bai, L. Chen, X.-F. Chen, S.-B. Dong, B. Du, J.-N. Fu, Z.-W. Han, J.-L. Hou, Y.-H. Hou, W. Hou, D.-K. Jiang, X. Kong, L.-F. Li, C. Liu, J.-M. Liu, L. Qin, J.-R. Shi, H. Tian, H. Wu, C.-J. Wu, J.-W. Xie, H.-T. Zhang, S. Zhang, G. Zhao, Y.-H. Zhao, J. Zhong, W.-K. Zong, F. Zuo

Comments: published by ApJs. 13 pages, 13 figures

Journal-ref: 2019ApJS..244...27W

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA); Instrumentation and Methods for Astrophysics (astro-ph.IM)

[92]  arXiv:1908.05625 (replaced) [pdf, other]

Title: An Improved Distance to NGC 4258 and its Implications for the Hubble Constant

Authors: M. J. Reid, D. W. Pesce, A. G. Riess

Comments: As will be published in ApJ (15 pages; 4 tables; 1 figure)

Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

[93]  arXiv:1908.08765 (replaced) [pdf, ps, other]

Title: Reduction of the Uncertainty in the Atmospheric Neutrino Flux Prediction Below 1 GeV Using Accurately Measured Atmospheric Muon Flux

Authors: M. Honda, M. Sajjad Athar, T. Kajita, K. Kasahara, S. Midorikawa

Comments: 14 pages, 30 fugures

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[94]  arXiv:1909.04152 (replaced) [pdf, other]

Title: The Overarching Framework of Core-Collapse Supernova Explosions as Revealed by 3D Fornax Simulations

Authors: Adam Burrows, David Radice, David Vartanyan, Hiroki Nagakura, M. Aaron Skinner, Joshua Dolence

Comments: Accepted to Monthly Notices of the Royal Astronomical Society

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)

[95]  arXiv:1909.04545 (replaced) [pdf, other]

Title: SN2018kzr: a rapidly declining transient from the destruction of a white dwarf

Authors: Owen R. McBrien, Stephen J. Smartt, Ting-Wan Chen, Cosimo Inserra, James H. Gillanders, Stuart A. Sim, Anders Jerkstrand, Armin Rest, Stefano Valenti, Rupak Roy, Mariusz Gromadzki, Stefan Taubenberger, Andreas Flörs, Mark E. Huber, Ken C. Chambers, Avishay Gal-Yam, David R. Young, Matt Nicholl, Erkki Kankare, Ken W. Smith, Kate Maguire, Ilya Mandel, Simon Prentice, Ósmar Rodríguez, Jonathon Pineda Garcia, Claudia P. Gutiérrez, Lluís Galbany, Cristina Barbarino, Peter S. J. Clark, Jesper Sollerman, Shrinivas R. Kulkarni, Kishalay De, David A. H. Buckley, Arne Rau

Comments: 11 pages, 5 figures, 3 tables Accepted by ApJL on 2019 October 15

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[96]  arXiv:1909.09161 (replaced) [pdf, ps, other]

Title: Visual Orbits of Spectroscopic Binaries with the CHARA Array. II. The eclipsing binary HD 185912

Authors: Kathryn V. Lester, Douglas R. Gies, Gail H. Schaefer, Christopher D. Farrington, Zhao Guo, Rachel A. Matson, John D. Monnier, Theo ten Brummelaar, Judit Sturmann, Norman Vargas, Samuel A. Weiss

Comments: Accepted for publication in the Astronomical Journal. 13 pages, 8 figures. (updated references)

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

[97]  arXiv:1909.11621 (replaced) [pdf, other]

Title: Testing emission models on the extreme blazar 2WHSP J073326.7+515354 detected at very high energies with the MAGIC telescopes

Authors: MAGIC Collaboration: V. A. Acciari (1), S. Ansoldi (2,23), L. A. Antonelli (3), A. Arbet Engels (4), D. Baack (5), A. Babić (6), B. Banerjee (7), U. Barres de Almeida (8), J. A. Barrio (9), J. Becerra González (1), W. Bednarek (10), L. Bellizzi (11), E. Bernardini (12,16), A. Berti (13), J. Besenrieder (14), W. Bhattacharyya (12), C. Bigongiari (3), A. Biland (4), O. Blanch (15), G. Bonnoli (11), Ž. Bošnjak (6), G. Busetto (16), R. Carosi (17), G. Ceribella (14), M. Cerruti (25), Y. Chai (14), A. Chilingaryan (18), S. Cikota (6), S. M. Colak (15), U. Colin (14), E. Colombo (1), J. L. Contreras (9), J. Cortina (19), S. Covino (3), V. D'Elia (3), P. Da Vela (17), F. Dazzi (3), A. De Angelis (16), B. De Lotto (2), M. Delfino (15,26), J. Delgado (15,26), D. Depaoli (13), et al. (133 additional authors not shown)

Comments: MNRAS published

Journal-ref: 490, 2019, 2284-2299

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[98]  arXiv:1909.12840 (replaced) [pdf, other]

Title: Spectrally resolved cosmic ray hydrodynamics -- I. Spectral scheme

Authors: Philipp Girichidis, Christoph Pfrommer, Michal Hanasz, Thorsten Naab

Comments: 16 pages, MNRAS accepted, corrected typo in eq. (63)

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics of Galaxies (astro-ph.GA)

[99]  arXiv:1909.13504 (replaced) [pdf, other]

Title: Hybrid Numerical Simulations of Pulsar Magnetospheres

Authors: Ioannis Contopoulos, Jerome Petri, Petros Stefanou

Comments: 7 pages, 5 figures, Monthly Notices in press

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[100]  arXiv:1910.00719 (replaced) [pdf, other]

Title: Testing the radius scaling relation with ${\it Gaia}$ DR2 in the ${\it Kepler}$ field

Authors: Joel C. Zinn, Marc H. Pinsonneault, Daniel Huber, Dennis Stello, Keivan Stassun, Aldo Serenelli

Comments: Published in ApJ

Journal-ref: The Astrophysical Journal, Volume 885, Issue 2, article id. 166, 18 pp. (2019)

Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

[101]  arXiv:1910.07680 (replaced) [pdf, ps, other]

Title: Search for Astronomical Neutrinos from Blazar TXS0506+056 in Super-Kamiokande

Authors: K. Hagiwara, K. Abe, C. Bronner, Y. Hayato, M. Ikeda, H. Ito, J. Kameda, Y. Kataoka, Y. Kato, Y. Kishimoto, Ll. Marti, M. Miura, S. Moriyama, T. Mochizuki, M. Nakahata, Y. Nakajima, S. Nakayama, T. Okada, K. Okamoto, A. Orii, G. Pronost, H. Sekiya, M. Shiozawa, Y. Sonoda, A. Takeda, A. Takenaka, H. Tanaka, T. Yano, R. Akutsu, T. Kajita, K. Okumura, R. Wang, J. Xia, D. Bravo-Berguno, L. Labarga, P. Fernandez, F. d. M. Blaszczyk, E. Kearns, J. L. Raaf, J. L. Stone, L. Wan, T. Wester, J. Bian, N. J. Griskevich, W. R. Kropp, S. Locke, S. Mine, M. B. Smy, H. W. Sobel, V. Takhistov, P. Weatherly, K. S. Ganezer, J. Hill, J. Y. Kim, I. T. Lim, R. G. Park, B. Bodur, K. Scholberg, C. W. Walter, A. Coffani, O. Drapier, M. Gonin, Th. A. Mueller, P. Paganini, T. Ishizuka, T. Nakamura, J. S. Jang, J. G. Learned, et al. (105 additional authors not shown)

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

[102]  arXiv:1910.11887 (replaced) [pdf, other]

Title: Cusp or core? Revisiting the globular cluster timing problem in Fornax

Authors: Noah Meadows, Julio F. Navarro, Isabel Santos-Santos, Alejandro Benitez-Llambay, Carlos Frenk

Comments: 7 pages, 4 figures. Submitted to MNRAS

Subjects: Astrophysics of Galaxies (astro-ph.GA)

[103]  arXiv:1910.12879 (replaced) [pdf, other]

Title: A detailed study of Andromeda XIX, an extreme local analogue of ultra diffuse galaxies

Authors: Michelle L. M. Collins, Erik J. Tollerud, R. Michael Rich, Rodrigo A. Ibata, Nicolas F. Martin, Scott C. Chapman, Karoline M. Gilbert, Janet Preston

Comments: 15 pages, (plus 5 extra for appendices), 15 figures, MNRAS accepted (no significant revision from previous version)

Subjects: Astrophysics of Galaxies (astro-ph.GA)

[104]  arXiv:1911.02012 (replaced) [pdf, other]

Title: TOI-132 b: A short-period planet in the Neptune desert transiting a $V=11.3$ G-type star

Authors: Matías R. Díaz, James S. Jenkins, Davide Gandolfi, Eric D. Lopez, Maritza G. Soto, Pía Cortés-Zuleta, Zaira M. Berdiñas, Keivan G. Stassun, Karen A. Collins, José I. Vines, Carl Ziegler, Malcolm Fridlund, Eric J. N. Jensen, Felipe Murgas, Alexandre Santerne, Paul A. Wilson, Massimiliano Esposito, Artie P. Hatzes, Marshall C. Johnson, Kristine W. F. Lam, John H. Livingston, Vincent Van Eylen, Norio Narita, César Briceño, Kevin I. Collins, Szilard Csizmadia, Michael Fausnaugh, Tianjun Gan, Iska Georgieva, Ana Glidden, Jon M. Jenkins, David W. Latham, Nicholas M. Law, Andrew W. Mann, Savita Mathur, Ismael Mireles, Robert Morris, Enric Pallé, Carina M. Persson, Stephen Rinehart, Mark E. Rose, Sara Seager, Jeffrey C. Smith, Thiam-Guan Tan, Andrei Tokovinin, et al. (3 additional authors not shown)

Comments: 12 pages, 10 figures, 4 tables. Submitted to MNRAS. Comments welcome. Missing labels, Typos fixed

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

[105]  arXiv:1911.02398 (replaced) [pdf, other]

Title: Detecting the relativistic galaxy bispectrum

Authors: Roy Maartens, Sheean Jolicoeur, Obinna Umeh, Chris Clarkson, Stefano Camera, Eline M. De Weerd

Comments: 13 pages, 10 figures

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

[106]  arXiv:1911.03488 (replaced) [pdf, other]

Title: Galactic Positron Excess from Selectively Enhanced Dark Matter Annihilation?

Authors: Anirban Das, Basudeb Dasgupta, Anupam Ray (Tata Inst., Mumbai)

Comments: minor changes: text improved, refs added, Fig.6 with correct parameters

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)

[107]  arXiv:1911.06693 (replaced) [pdf, other]

Title: Towards a deeper understanding of the physics driving galaxy quenching -- inferring trends in the gas content via extinction

Authors: Joanna Piotrowska, Asa F. L. Bluck, Roberto Maiolino, Alice Concas, Yingjie Peng

Comments: Accepted for publication in MNRAS Letters

Subjects: Astrophysics of Galaxies (astro-ph.GA)

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