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New submissions for Tue, 28 Jan 20

[1]  arXiv:2001.09152 [pdf, ps, other]

Title: Distant foreground and the Planck-derived Hubble constant

Authors: V.N. Yershov, A.A. Raikov, N.Yu. Lovyagin, N.P.M. Kuin, E.A. Popova

Comments: 5 pages, 4 figures, 1 table

Journal-ref: Monthly Notices of the Royal Astronomical Society, 2020, staa189

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

It is possible to reduce the discrepancy between the local measurement of the cosmological parameter $H_0$ and the value derived from the {\it Planck} measurements of the Cosmic Microwave Background (CMB) by considering contamination of the CMB by emission from some medium around distant extragalactic sources, such as extremely cold coarse-grain dust. Though being distant, such a medium would still be in the foreground with respect to the CMB, and, as any other foreground, it would alter the CMB power spectrum. This could contribute to the dispersion of CMB temperature fluctuations. By generating a few random samples of CMB with different dispersions, we have checked that the increased dispersion leads to a smaller estimated value of $H_0$, the rest of the cosmological model parameters remaining fixed. This might explain the reduced value of the {\it Planck}-derived parameter $H_0$ with respect to the local measurements. The signature of the distant foreground in the CMB traced by SNe was previously reported by the authors of this paper -- we found a correlation between the SN redshifts, $z_{\rm SN}$, and CMB temperature fluctuations at the SNe locations, $T_{\rm SN}$. Here we have used the slopes of the regression lines $T_{\rm SN}\,/\,z_{\rm SN}$ corresponding to different {\it Planck} wave bands in order to estimate the possible temperature of the distant extragalactic medium, which turns out to be very low, about 5\,K. The most likely ingredient of this medium is coarse-grain ({\it grey}) dust, which is known to be almost undetectable, except for the effect of dimming remote extragalactic sources.

[2]  arXiv:2001.09153 [pdf, other]

Title: Magnetohydrodynamic Simulations of Binary Neutron Star Mergers in General Relativity: Effects of Magnetic Field Orientation on Jet Launching

Authors: Milton Ruiz, Antonios Tsokaros, Stuart L. Shapiro

Comments: 16 pages, 12 figures

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

Binary neutron star (NSNS) mergers can be sources of gravitational waves coincident with electromagnetic counterpart emission. To solidify their role as multimessenger sources, we present fully 3D, general relativistic, magnetohydrodynamic simulations of spinning NSNSs initially on quasicircular orbits that merge and undergo delayed collapse to a black hole (BH). The NSNSs consist of two identical stars modeled as $\Gamma=2$ polytropes with spin $\chi_{NS}= 0.36$ aligned along the direction of the total orbital angular momentum $L$. Each star is initially threaded by a dynamical unimportant interior dipole B-field. The field is extended into the exterior where a nearly force-free magnetosphere resembles that of a pulsar. The magnetic dipole moment $\mu$ is either aligned or perpendicular to $L$ and has the same initial magnitude for each orientation. For comparison, we also impose symmetry across the orbital plane in one case where $\mu$ in both stars is aligned along $L$. We find that the lifetime of the transient hypermassive neutron star remnant, the jet launching time, and the ejecta are very sensitive to the B-field orientation. By contrast, the physical properties of the BH + disk remnant, such as the mass and spin of the BH, the accretion rate, and the electromagnetic luminosity, are roughly independent of the initial B-field orientation. In addition, we find imposing symmetry across the orbital plane does not play a significant role in the final outcome of the mergers. Our results show that an incipient jet emerges only when the seed B-field has a sufficiently large-scale poloidal component aligned to $L$. The lifetime [$\Delta t\gtrsim 140(M_{NS}/1.625M_\odot)\rm ms$] and Poynting luminosities [$L_{EM}\simeq 10^{52}$erg/s] of the jet, when it forms, are consistent with typical short gamma-ray bursts, as well as with the Blandford--Znajek mechanism for launching jets.

[3]  arXiv:2001.09154 [pdf, other]

Title: The star formation histories of z~1 post-starburst galaxies

Authors: Vivienne Wild, Laith Taj Aldeen, Adam Carnall, David Maltby, Omar Almaini, Ariel Werle, Aaron Wilkinson, Kate Rowlands, Micol Bolzonella, Marco Castellano, Adriana Garguilo, Ross McLure, Laura Pentericci, Lucia Pozzetti

Comments: 22 pages, 16 figures, submitted to MNRAS on 10th December 2019 and awaiting referees report. Comments welcome

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

We present the star formation histories of 39 galaxies with high quality rest-frame optical spectra at 0.5<z<1.3 selected to have strong Balmer absorption lines and/or Balmer break, and compare to a sample of spectroscopically selected quiescent galaxies at the same redshift. Photometric selection identifies a majority of objects that have clear evidence for a recent short-lived burst of star formation within the last 1.5 Gyr, i.e. "post-starburst" galaxies, however we show that good quality continuum spectra are required to obtain physical parameters such as burst mass fraction and burst age. Dust attenuation appears to be the primary cause for misidentification of post-starburst galaxies, leading to contamination in spectroscopic samples where only the [OII] emission line is available, as well as a small fraction of objects lost from photometric samples. The 31 confirmed post-starburst galaxies have formed 40-90% of their stellar mass in the last 1-1.5 Gyr. We use the derived star formation histories to find that the post-starburst galaxies are visible photometrically for 0.5-1 Gyr. This allows us to update a previous analysis to suggest that 25-50% of the growth of the red sequence at z~1 could be caused by a starburst followed by rapid quenching. We use the inferred maximum historical star formation rates of several 100-1000 Msun/yr and updated visibility times to confirm that sub-mm galaxies are likely progenitors of post-starburst galaxies. The short quenching timescales of 100-200 Myr are consistent with cosmological hydrodynamic models in which rapid quenching is caused by the mechanical expulsion of gas due to an AGN.

[4]  arXiv:2001.09157 [pdf, other]

Title: Mass-to-Light Ratios of Spatially Resolved Stellar Populations in M31

Authors: O. Grace Telford, Julianne J. Dalcanton, Benjamin F. Williams, Eric F. Bell, Andrew E. Dolphin, Meredith J. Durbin, Yumi Choi

Comments: Accepted to ApJ. Main text is 25 pages, including 15 figures

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

A galaxy's stellar mass-to-light ratio ($M_\star/L$) is a useful tool for converting luminosity to stellar mass ($M_\star$). However, the practical utility of $M_\star/L$ inferred from stellar population synthesis (SPS) models is limited by mismatches between the real and assumed models for star formation history (SFH) and dust geometry, both of which vary within galaxies. Here, we measure spatial variations in $M_\star/L$ and their dependence on color, star formation history, and dust across the disk of M31, using a map of $M^\mathrm{CMD}_\star$ derived from color-magnitude diagrams of resolved stars in the Panchromatic Hubble Andromeda Treasury (PHAT) survey. First, we find comparable scatter in $M_\star/L$ for the optical and mid-IR, contrary to the common idea that $M_\star/L$ is less variable in the IR. Second, we confirm that $M_\star/L$ is correlated with color for both the optical and mid-IR and report color vs. $M_\star/L$ relations (CMLRs) in M31 for filters used in the Sloan Digital Sky Survey (SDSS) and Widefield Infrared Survey Explorer (WISE). Third, we show that the CMLR residuals correlate with recent SFH, such that quiescent regions are offset to higher $M_\star/L$ than star-forming regions at a fixed color. The mid-IR CMLR, however, is not linear due to the high scatter of $M_\star/L$ in star-forming regions. Finally, we find a flatter optical CMLR than any SPS-based CMLRs in the literature. We show this is an effect of dust geometry, which is typically neglected but should be accounted for when using optical data to map $M_\star/L$.

[5]  arXiv:2001.09158 [pdf, other]

Title: Curvature Perturbations From Stochastic Particle Production During Inflation

Authors: Marcos A. G. Garcia, Mustafa A. Amin, Daniel Green

Comments: 68 pages, 23 figures

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

We calculate the curvature power spectrum sourced by spectator fields that are excited repeatedly and non-adiabatically during inflation. In the absence of detailed information of the nature of spectator field interactions, we consider an ensemble of models with intervals between the repeated interactions and interaction strengths drawn from simple probabilistic distributions. We show that the curvature power spectra of each member of the ensemble shows rich structure with many features, and there is a large variability between different realizations of the same ensemble. Such features can be probed by the cosmic microwave background (CMB) and large scale structure observations. They can also have implications for primordial black hole formation and CMB spectral distortions.
The geometric random walk behavior of the spectator field allows us to calculate the ensemble-averaged power spectrum of curvature perturbations semi-analytically. For sufficiently large stochastic sourcing, the ensemble-averaged power spectrum shows a scale dependence arising from the time spent by modes outside the horizon during the period of particle production, in spite of there being no preferred scale in the underlying model. We find that the magnitude of the ensemble-averaged power spectrum overestimates the typical power spectra in the ensemble because the ensemble distribution of the power spectra is highly non-Gaussian with fat tails.

[6]  arXiv:2001.09160 [pdf, other]

Title: Exploring Primordial Black Holes from Multiverse with Optical Telescopes

Authors: Alexander Kusenko, Misao Sasaki, Sunao Sugiyama, Masahiro Takada, Volodymyr Takhistov, Edoardo Vitagliano

Comments: 6 pages, 3 figures

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

Primordial black holes (PBHs) are a viable candidate for dark matter if the PBH masses are in the currently unconstrained "sublunar" mass range. We revisit the possibility that PBHs were produced by nucleation of false vacuum bubbles during inflation. We show that this scenario can produce a population of PBHs that simultaneously accounts for all dark matter, explains the candidate event in Subaru Hyper Suprime-Cam (HSC) data, and contains both heavy black holes as observed by LIGO and very heavy seeds of super-massive black holes. We demonstrate with numerical studies that future observations of HSC, as well as other optical surveys, such as LSST, will be able to provide a definitive test for this generic PBH formation mechanism if it is the dominant source of dark matter.

[7]  arXiv:2001.09175 [pdf, other]

Title: A hot terrestrial planet orbiting the bright M dwarf L 168-9 unveiled by TESS

Authors: N. Astudillo-Defru, R. Cloutier, S. X. Wang, J. Teske, R. Brahm, C. Hellier, G. Ricker, R. Vanderspek, D. Latham, S. Seager, J. N. Winn, J. M. Jenkins, K. A. Collins, K. G. Stassun, C. Ziegler, J. M. Almenara, D. R. Anderson, E. Artigau, X. Bonfils, F. Bouchy, C. Briceño, R. P. Butler, D. Charbonneau, D. M. Conti, J. Crane, I. J .M. Crossfield, M. Davies, X. Delfosse, R. F. Díaz, R. Doyon, D. Dragomir, J. D. Eastman, N. Espinoza, Z. Essack, F. Feng, P. Figueira, T. Forveille, T. Gan, A. Glidden, N. Guerrero, R. Hart, Th. Henning, E. P. Horch, G. Isopi, J. S. Jenkins, A. Jordán, J. F. Kielkopf, N. Law, C. Lovis, F. Mallia, A. W. Mann, J. R. de Medeiros, C. Melo, R. E. Mennickent, L. Mignon, F. Murgas, D. A. Nusdeo, F. Pepe, H. M. Relles, M. Rose, N. C. Santos, D. Ségransan, et al. (8 additional authors not shown)

Comments: 14 pages, 8 figures, 3 tables. Accepted for publication in astronomy and Astrophysics

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

We report the detection of a transiting super-Earth-sized planet (R=1.39+-0.09 Rearth) in a 1.4-day orbit around L 168-9 (TOI-134),a bright M1V dwarf (V=11, K=7.1) located at 25.15+-0.02 pc. The host star was observed in the first sector of the Transiting Exoplanet Survey Satellite (TESS) mission and, for confirmation and planet mass measurement, was followed up with ground-based photometry, seeing-limited and high-resolution imaging, and precise radial velocity (PRV) observations using the HARPS and PFS spectrographs. Combining the TESS data and PRV observations, we find the mass of L168-9 b to be 4.60+-0.56 Mearth, and thus the bulk density to be 1.74+0.44-0.33 times larger than that of the Earth. The orbital eccentricity is smaller than 0.21 (95% confidence). This planet is a Level One Candidate for the TESS Mission's scientific objective - to measure the masses of 50 small planets - and is one of the most observationally accessible terrestrial planets for future atmospheric characterization.

[8]  arXiv:2001.09208 [pdf, other]

Title: A random-walk model for dark matter halo spins

Authors: Andrew Benson (1), Christoph Behrens (2), Yu Lu (1) ((1) Carnegie Institution for Science, (2) Institut fur Astrophysik, Georg-August Universitat Gottingen)

Comments: 9 pages, submitted to MNRAS, comments welcome

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

We extend the random-walk model of Vitvitska et al. for predicting the spins of dark matter halos from their merger histories. Using updated merger rates, orbital parameter distributions, and N-body constraints we show that this model can accurately reproduce the distribution of spin parameters measured in N-body simulations when we include a weak correlation between the spins of halos and the angular momenta of infalling subhalos. We further show that this model is in approximate agreement with the correlation of the spin magnitude over time as determined from N-body simulations, while it slightly underpredicts the correlation in the direction of the spin vector measured from the same simulations. This model is useful for predicting spins from merger histories derived from non-N-body sources, thereby circumventing the need for very high resolution simulations to permit accurate measurements of spins. It may be particularly relevant to modeling systems which accumulate angular momentum from halos over time (such as galactic disks)---we show that this model makes small but significant changes in the distribution of galactic disk sizes computed using the Galacticus semi-analytic galaxy formation model.

[9]  arXiv:2001.09210 [pdf, other]

Title: Nonlinear optics in strongly magnetized pair plasma, with applications to FRBs

Authors: Maxim Lyutikov (Purdue University)

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Plasma Physics (physics.plasm-ph)

Intense radiation field can modify plasma properties, the corresponding refractive index, and lead to such nonlinear propagation effects as self-focusing. We estimate the corresponding effects in pair plasma, both in unmagnetized and strongly magnetically dominated case. First, in the unmagnetized pair plasma the ponderomotive force does not lead to charge separation, but to density depletion. Second, for astrophysically relevant plasmas of pulsar magnetospheres, (and possible loci of Fast Radio Bursts), where cyclotron frequency $\omega_B$ dominates over plasma frequency $\omega_p$ and the frequency of the electromagnetic wave, $\omega_B \gg \omega_p,\, \omega$, we show that (i) there is virtually no nonlinearity due to changing effective mass in the field of the wave; (ii) ponderomotive force is $F_p^{(B)} =- {m_e c^2}/({4 B_0^2}) \nabla E^2$; it is reduced by a factor $(\omega/\omega_B)^2$ if compared to the unmagnetized case ($B_0$ is the external magnetic field and $E$ is the electric field of the wave); (iii) for radiation beam propagating along constant magnetic field in pair plasma with density $n_\pm$, the ponderomotive force leads to appearance of circular currents that lead to the decrease of the field within the beam by a factor $\Delta B/B_0 = 2\pi n_\pm m_e c^2 {E^2}/{B_0^4}$. Applications to the physics of FRBs are discussed; we conclude that for parameters of FRB's the dominant magnetic field completely suppresses nonlinear radiation effects.

[10]  arXiv:2001.09211 [pdf]

Title: Modal noise mitigation for high-precision spectroscopy using a photonic reformatter

Authors: Fraser A. Pike (1), Aurélien Benoît (1), David G. MacLachlan (1), Robert J. Harris (2), Itandehui Gris Sánchez (3 and 4), David Lee (5), Tim A. Birks (3), Robert R. Thomson (1) ((1) Heriot-Watt University, Edinburgh, UK, (2) Zentrum für Astronomie der Universität Heidelberg, Germany, (3) University of Bath, UK, (4) Currently with ITEAM Research Institute, Valencia, Spain, (5) STFC UK Astronomy Technology Centre, UK)

Comments: 13 pages, 9 figures (including appendix)

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

Recently, we demonstrated how an astrophotonic light reformatting device, based on a multicore fibre photonic lantern and a three-dimensional waveguide component, can be used to efficiently reformat the point spread function of a telescope to a diffraction-limited psuedo-slit [arXiv:1512.07309]. Here, we demonstrate how such a device can also efficiently mitigate modal noise -- a potential source of instability in high resolution multi-mode fibre-fed spectrographs). To investigate the modal noise performance of the photonic reformatter, we have used it to feed light into a bench-top near-infrared spectrograph (R {\approx} 9,500, {\lambda} {\approx} 1550 nm). One approach to quantifying the modal noise involved the use of broadband excitation light and a statistical analysis of how the overall measured spectrum was affected by variations in the input coupling conditions. This approach indicated that the photonic reformatter could reduce modal noise by a factor of six when compared to a multi-mode fibre with a similar number of guided modes. Another approach to quantifying the modal noise involved the use of multiple spectrally narrow lines, and an analysis of how the measured barycentres of these lines were affected by variations in the input coupling. Using this approach, the photonic reformatter was observed to suppress modal noise to the level necessary to obtain spectra with stability close to that observed when using a single mode fibre feed. These results demonstrate the potential of using photonic reformatters to enable efficient multi-mode spectrographs that operate at the diffraction limit and are free of modal noise, with potential applications including radial velocity measurements of M-dwarfs.

[11]  arXiv:2001.09213 [pdf, other]

Title: The Megamaser Cosmology Project. XIII. Combined Hubble constant constraints

Authors: D. W. Pesce, J. A. Braatz, M. J. Reid, A. G. Riess, D. Scolnic, J. J. Condon, F. Gao, C. Henkel, C. M. V. Impellizzeri, C. Y. Kuo, K. Y. Lo

Comments: 13 pages, 1 figure, submitted to ApJL

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

We present a measurement of the Hubble constant made using geometric distance measurements to megamaser-hosting galaxies. We have applied an improved approach for fitting maser data and obtained better distance estimates for four galaxies previously published by the Megamaser Cosmology Project: UGC 3789, NGC 6264, NGC 6323, and NGC 5765b. Combining these updated distance measurements with those for the maser galaxies CGCG 074-064 and NGC 4258, and assuming a fixed velocity uncertainty of 250 km s$^{-1}$ associated with peculiar motions, we constrain the Hubble constant to be $H_0 = 73.9 \pm 3.0$ km s$^{-1}$ Mpc$^{-1}$ independent of distance ladders and the cosmic microwave background. This best value relies solely on maser-based distance and velocity measurements, and it does not use any peculiar velocity corrections. Different approaches for correcting peculiar velocities do not modify $H_0$ by more than ${\pm}1{\sigma}$, with the full range of best-fit Hubble constant values spanning 71.8-76.9 km s$^{-1}$ Mpc$^{-1}$. We corroborate prior indications that the local value of $H_0$ exceeds the early-Universe value, with a confidence level varying from 95-99% for different treatments of the peculiar velocities.

[12]  arXiv:2001.09222 [pdf, other]

Title: Progress in unveiling extreme particle acceleration in persistent astrophysical jets

Authors: Jonathan Biteau, Elisa Prandini, Luigi Costamante, Martin Lemoine, Paolo Padovani, Elisa Pueschel, Elisa Resconi, Fabrizio Tavecchio, Andrew Taylor, Andreas Zech

Comments: 8 pages, 4 figures, 1 table. Submitted version

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

The most powerful persistent accelerators in the Universe are jetted active galaxies. Galaxies whose jets are directed towards Earth, so called blazars, dominate the extragalactic gamma-ray sky. Still, most of the highest-energy accelerators likely elude detection. These extreme blazars, whose radiated energy can peak beyond 10 TeV, are ideal targets to study particle acceleration and radiative processes, and may provide links to cosmic rays and astrophysical neutrinos. The growing number of extreme blazars observed at TeV energies has been critical for the emergence of gamma-ray cosmology, including measurements of the extragalactic background light, tight bounds on the intergalactic magnetic field, and constraints on exotic physics at energies inaccessible with human-made accelerators. Tremendous progress is expected in the decade to come, particularly with the deployment of the Cherenkov Telescope Array.

[13]  arXiv:2001.09229 [pdf, other]

Title: Non-linear matter power spectrum without screening dynamics modelling in $f(R)$ gravity

Authors: Cheng-Zong Ruan, Tong-Jie Zhang, Bin Hu

Comments: Accepted in MNRAS

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

Halo model is a physically intuitive method for modelling the non-linear power spectrum, especially for the alternatives to the standard $\Lambda$CDM models. In this paper, we exam the Sheth-Tormen barrier formula adopted in the previous \texttt{CHAM} method \citep{2018MNRAS.476L..65H}. As an example, we model the ellipsoidal collapse of top-hat dark matter haloes in $f(R)$ gravity. A good agreement between Sheth-Tormen formula and our result is achieved. The relative difference in the ellipsoidal collapse barrier is less than or equal to $1.6\%$. Furthermore, we verify that, for F4 and F5 cases of Hu-Sawicki $f(R)$ gravity, the screening mechanism do not play a crucial role in the non-linear power spectrum modelling up to $k\sim1[h/{\rm Mpc}]$. We compare two versions of modified gravity modelling, namely with/without screening. We find that by treating the effective Newton constant as constant number ($G_{\rm eff}=4/3G_N$) is acceptable. The scale dependence of the gravitational coupling is sub-relevant. The resulting spectra in F4 and F5, are in $0.1\%$ agreement with the previous \texttt{CHAM} results. The published code is accelerated significantly. Finally, we compare our halo model prediction with N-body simulation. We find that the general spectrum profile agree, qualitatively. However, via the halo model approach, there exists a systematic under-estimation of the matter power spectrum in the co-moving wavenumber range between $0.3 h/{\rm Mpc}$ and $3 h/{\rm Mpc}$. These scales are overlapping with the transition scales from two halo term dominated regimes to those of one halo term dominated.

[14]  arXiv:2001.09235 [pdf, other]

Title: Capture and migration of Jupiter and Saturn in mean motion resonance in a gaseous protoplanetary disc

Authors: Raul O. Chametla, Gennaro D'Angelo, Mauricio Reyes-Ruiz, F. Javier Sanchez-Salcedo

Comments: Accepted for publication in MNRAS (14 pages, 10 figures, 3 tables)

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

We study the dynamical evolution of Jupiter and Saturn embedded in a gaseous, solar-nebula-type disc by means of hydrodynamics simulations with the FARGO2D1D code. We study the evolution for different initial separations of the planets' orbits, Delta a_SJ , to investigate whether they become captured in mean motion resonance (MMR) and the direction of the subsequent migration of the planet (inward or outward). We also provide an assessment of the planet's orbital dynamics at different epochs of Saturn's growth. We find that the evolution of initially compact orbital configurations is dependent on the value of Delta a_SJ . This implies that an evolution as that proposed in the Grand Tack model depends on the precise initial orbits of Jupiter and Saturn and on the timescales for their formation. Capture in the 1:2 MMR and inward or (nearly) stalled migration are highly favoured. Within its limits, our work suggests that the reversed migration, associated with the resonance capture of Jupiter and Saturn, may be a low probability evolutionary scenario, so that other planetary systems with giant planets are not expected to have experienced a Grand Tack-like evolutionary path.

[15]  arXiv:2001.09260 [pdf, other]

Title: Cosmological model insensitivity of local $H_0$ from the Cepheid distance ladder

Authors: S. Dhawan, D. Brout, D. Scolnic, A. Goobar, A.G. Riess, V. Miranda

Comments: 11 pages, 3 figures, submitted to ApJ. Comments welcome

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

The observed tension ($\sim 9\%$ difference) between the local distance ladder measurement of the Hubble constant, $H_0$, and its value inferred from the cosmic microwave background (CMB) could hint at new, exotic, cosmological physics. We test the impact of the assumption about the expansion history of the universe ($0.01<z<2.3$) on the local distance ladder estimate of $H_0$. In the fiducial analysis, the Hubble flow Type Ia supernova (SN~Ia) sample is truncated to $z < 0.15$ and the deceleration parameter ($q_0$) fixed to -0.55. We create realistic simulations of the calibrator and Pantheon samples and account for a full systematics covariance between these two sets. We fit several physically motivated dark energy models and derive combined constraints from calibrator and Pantheon SNe~Ia and simultaneously infer $H_0$ and dark energy properties. We find that the assumption on the dark energy model does not significantly change the local distance ladder value of $H_0$, with a maximum difference ($\Delta H_0$) between the inferred value for different models of 0.47 km$^{-1}$ s$^{-1}$ Mpc $^{-1}$, i.e. a 0.6$\%$ shift in $H_0$, significantly smaller than the observed tension. Additional freedom in the dark energy models does not increase the error in the inferred value of $H_0$. Including systematics covariance between the calibrators, low redshift SNe, and high redshift SNe can induce small shifts in the inferred value for $H_0$. The SN~Ia systematics in this study contribute $\lesssim 0.8 \%$ to the total uncertainty on $H_0$.

[16]  arXiv:2001.09269 [pdf, other]

Title: Atmosphere Origins for Exoplanet Sub-Neptunes

Authors: Edwin S. Kite, Bruce Fegley Jr., Laura Schaefer, Eric Ford

Comments: Accepted by ApJ

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

Planets with 2 $R_{\oplus}$ < $R$ < 3 $R_{\oplus}$ and orbital period $<$100 d are abundant; these sub-Neptune exoplanets are not well understood. For example, $Kepler$ sub-Neptunes are likely to have deep magma oceans in contact with their atmospheres, but little is known about the effect of the magma on the atmosphere. Here we study this effect using a basic model, assuming that volatiles equilibrate with magma at $T$ $\sim$ 3000 K. For our Fe-Mg-Si-O-H model system, we find that chemical reactions between the magma and the atmosphere and dissolution of volatiles into the magma are both important. Thus, magma matters. For H, most moles go into the magma, so the mass target for both H$_2$ accretion and H$_2$ loss models is weightier than is usually assumed. The known span of magma oxidation states can produce sub-Neptunes that have identical radius but with total volatile masses varying by 20-fold. Thus, planet radius is a proxy for atmospheric composition but not for total volatile content. This redox diversity degeneracy can be broken by measurements of atmosphere mean molecular weight. We emphasise H$_2$ supply by nebula gas, but also consider solid-derived H$_2$O. We find that adding H$_2$O to Fe probably cannot make enough H$_2$ to explain sub-Neptune radii because $>$10$^3$-km thick outgassed atmospheres have high mean molecular weight. The hypothesis of magma-atmosphere equilibration links observables such as atmosphere H$_2$O/H$_2$ ratio to magma FeO content and planet formation processes. Our model's accuracy is limited by the lack of experiments (lab and/or numerical) that are specific to sub-Neptunes; we advocate for such experiments.

[17]  arXiv:2001.09283 [pdf, other]

Title: On the aspect ratio of Oumuamua: less elongated shape for irregular surface properties

Authors: A. Vazan, R. Sari

Comments: 7 pages, accepted for publication in MNRAS

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

The large brightness variation in the observed lightcurve of Oumuamua is probably related to its shape, i.e., to the ratio between its longest axis and its shortest axis (aspect ratio). Several approaches found the aspect ratio of Oumuamua to be unusually elongated. Moreover, the spin axis orientation has to be almost perpendicular to the observer in order to obtain such an extreme lightcurve, a configuration which is unlikely. However, interstellar Oumuamua may have different surface properties than we know in our solar system. Therefore, in this work we widen the parameter space for surface properties beyond the asteroid-like models and study its effect on the lightcurve of Oumuamua. We calculate reflection from a rotating ellipsoidal object for four models: Lambertian reflection, specular reflection, single scattering diffusive and backscatter. We then calculate the probability to obtain a lightcurve ratio larger than the observed, as a function of the object aspect ratio, assuming an isotopic spin orientation distribution. We find the elongation of Oumuamua to be less extreme for the Lambertian and specular reflection models. Consequently, the probability to observe the lightcurve ratio of Oumuamua given its unknown spin axis orientation is larger for those models. We conclude that different surface reflection properties may suggest alternatives to the extreme shape of Oumuamua, relieving the need for complicated formation scenario, extreme albedo variation, or unnatural origin. Although the models suggested here are for ideal ellipsoidal shape and ideal reflection method, the results emphasize the importance of surface properties for the derived aspect ratio.

[18]  arXiv:2001.09348 [pdf, other]

Title: Probabilistic fibre-to-target assignment algorithm for multi-object spectroscopic surveys

Authors: E. Tempel, P. Norberg, T. Tuvikene, T. Bensby, C. Chiappini, N. Christlieb, M.-R. L. Cioni, J. Comparat, L. J. M. Davies, G. Guiglion, A. Koch, G. Kordopatis, M. Krumpe, J. Loveday, A. Merloni, G. Micheva, I. Minchev, B. F. Roukema, J. G. Sorce, E. Starkenburg, J. Storm, E. Swann, W. F. Thi, G. Traven, R. S. de Jong

Comments: 19 pages, 18 figures, submitted to A&A

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

Context. Several new multi-object spectrographs are currently planned or under construction that are capable of observing thousands of Galactic and extragalactic objects simultaneously.
Aims. In this paper we present a probabilistic fibre-to-target assignment algorithm that takes into account spectrograph targeting constraints and is capable of dealing with multiple concurrent surveys. We present this algorithm using the 4-metre Multi-Object Spectroscopic Telescope (4MOST) as an example.
Methods. The key idea of the proposed algorithm is to assign probabilities to fibre-target pairs. The assignment of probabilities takes into account the fibre positioner's capabilities and constraints. Additionally, these probabilities include requirements from surveys and take into account the required exposure time, number density variation and angular clustering of targets across each survey. The main advantage of a probabilistic approach is that it allows for accurate and easy computation of the target selection function - the probability of observing a target, given an input catalogue - for the different surveys.
Results. The probabilistic fibre-to-target assignment allows us to achieve maximally uniform completeness within a single field of view. The proposed algorithm maximises the fraction of successfully observed targets whilst minimising the selection bias as a function of exposure time. In the case of several concurrent surveys, the algorithm maximally satisfies the scientific requirements of each survey and no specific survey is penalised or prioritised.
Conclusions. The algorithm presented is a proposed solution for the 4MOST project that allows an unbiased targeting of many simultaneous surveys. With some modifications the algorithm may also be applied to other multi-object spectroscopic surveys.

[19]  arXiv:2001.09355 [pdf, other]

Title: Dissecting the regions around IceCube high-energy neutrinos: growing evidence for the blazar connection

Authors: P. Giommi, T. Glauch, P. Padovani, E. Resconi, A. Turcati, Y.L. Chang

Comments: 16 pages, 8 figures, submitted to MNRAS, revised version addressing all referee's comments

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

The association of two IceCube detections, the IceCube-170922A event and a neutrino flare, with the blazar TXS0506+056, has paved the way for the multimessenger quest for cosmic accelerators. IceCube has observed many other neutrinos but their origin remains unknown. To better understand the reason for the apparent lack of neutrino counterparts we have extended the comprehensive dissection of the sky area performed for the IceCube-170922A event to all the 70 public IceCube high-energy neutrinos that are well reconstructed and off the Galactic plane. Using the multi-frequency data available through the Open Universe platform, we have identified numerous candidate counterparts of IceCube events. We report here the classification of all the gamma-ray blazars found and the results of subsequent statistical tests. In addition, we have checked the 4LAC, 3FHL and 3HSP catalogues for potential counterparts. Following the dissection of all areas associated with IceCube neutrinos, we evaluate the data using a likelihood-ratio test and find a 3.23 sigma (post-trial) excess of HBLs and IBLs with a best-fit of 15 +/- 3.6 signal sources. This result, together with previous findings, consistently points to a growing evidence for a connection between IceCube neutrinos and blazars, the most energetic particle accelerators known in the Universe.

[20]  arXiv:2001.09376 [pdf, ps, other]

Title: Effects of Observational Data Shortage on Accuracy of Global Solar Activity Forecast

Authors: Irina N. Kitiashvili

Comments: 24 pages, 13 figures, 1 table, submitted to ApJ

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Chaotic Dynamics (nlin.CD)

Building a reliable forecast of solar activity is a long-standing problem that requires to accurately describe past and current global dynamics. However, synoptic observations of magnetic fields and subsurface flows became available relatively recently. In this paper, we present an investigation of effects of short observational data series on accuracy of solar cycle prediction. This analysis is performed using the annual sunspot number time-series applied to the Parker-Kleeorin-Ruzmaikin dynamo model and employing the Ensemble Kalman Filter (EnKF) data assimilation method. The testing of the cycle prediction accuracy is performed for the last six cycles (from Solar Cycle 19 to 24) by sequentially shortening the observational data series that are used for prediction of a target cycle, and evaluating the prediction accuracy according to specified criteria. According to the analysis, reliable activity predictions can be made using relatively short time-series of the sunspot number. It demonstrated that even two cycles of available observations allow us to obtain reasonable forecasts.

[21]  arXiv:2001.09385 [pdf, other]

Title: Gravitational slingshots around black holes in a binary

Authors: Fan Zhang

Comments: 20 pages, 8 figures

Journal-ref: Eur. Phys. J. Plus 135, 104 (2020)

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

The speed gain of a test mass from taking a gravitational slingshot around a celestial object (scattering centre) increases with the latter's speed and compactness (stronger deflection of the mass' trajectory becomes possible without it hitting the surface of the object). The black holes (BHs) in a tight binary (consisting of two black holes; we are not considering X-ray binaries), themselves moving at relativistic speeds, represent optimal scattering centres. Therefore, a sub-population of accreting matter particles, swept up into chaotic orbits around a BH binary, might repeatedly take slingshots and become accelerated to ultra-relativistic speeds (as seen by observers on Earth), ultimately escaping from the binary, as well as the fate of being devoured by a BH. The escaped particles can plausibly be observed on Earth as ultra-high-energy cosmic rays (UHECRs). Investigating such a possibility would require general relativistic slingshot formulae due to the high speeds involved and the close encounters with BHs. We derive them in this paper, and show that the percentage gain per slingshot in a particle's Lorentz factor remains undiminished even as the particle energizes up, thus demonstrating that the slingshot mechanism can in principal accelerate particles to extreme energies.

[22]  arXiv:2001.09457 [pdf, other]

Title: Structure of a collisionless pair jet in a magnetized electron-proton plasma: Flow-aligned magnetic field

Authors: Mark Eric Dieckmann, Martin Falk, Peter Steneteg, Doris Folini, Ingrid Hotz, Aida Nordman, Pierangelo Dell'Acqua, Anders Ynnerman, Rolf Walder

Comments: Accepted for publication by the Proceedings of Science. 10 pages, 4 figures

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

We present the results from a particle-in-cell (PIC) simulation that models the interaction between a spatially localized electron-positron cloud and an electron-ion plasma. The latter is permeated by a magnetic field that is initially spatially uniform and aligned with the mean velocity vector of the pair cloud. The pair cloud expels the magnetic field and piles it up into an electromagnetic piston. Its electromagnetic field is strong enough to separate the pair cloud from the ambient plasma in the direction that is perpendicular to the cloud propagation direction. The piston propagates away from the spine of the injected pair cloud and it accelerates the protons to a high nonrelativistic speed. The accelerated protons form an outer cocoon that will eventually become separated from the unperturbed ambient plasma by a fast magnetosonic shock. No electromagnetic piston forms at the front of the cloud and a shock is mediated here by the filamentation instability. The final plasma distribution resembles that of a hydrodynamic jet. Collisionless plasma jets may form in the coronal plasma of accreting black holes and the interaction between the strong magnetic field of the piston and the hot pair cloud may contribute to radio emissions by such objects.

[23]  arXiv:2001.09463 [pdf, ps, other]

Title: The Energy Sources of Double-peaked superluminous supernova PS1-12cil and luminous supernova SN 2012aa

Authors: Long Li, Shan-Qin Wang, Liang-Duan Liu, Xiang-Gao Wang, En-Wei Liang, Zi-Gao Dai

Comments: 11 pages, 3 figures, 3 tables, accepted for publication in ApJ

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

In this paper, we present the study for the energy reservoir powering the light curves (LCs) of PS1-12cil and SN 2012aa which are superluminous and luminous supernovae (SNe), respectively. The multi-band and bolometric LCs of these two SNe show unusual secondary bumps after the main peaks. The two-peaked LCs cannot be explained by any simple energy-source models (e.g., the $^{56}$Ni cascade decay model, the magnetar spin-down model, and the ejecta-circumstellar medium interaction model). Therefore, we employ the $^{56}$Ni plus ejecta-circumstellar medium (CSM) interaction (CSI) model, the magnetar plus CSI model, and the double CSI model to fit their bolometric LCs, and find that both these two SNe can be explained by the double CSI model and the magnetar plus CSI model. Based on the modeling, we calculate the the time when the shells were expelled by the progenitors: provided that they were powered by double ejecta-shell CSI, the inner and outer shells might be expelled $\sim 0.2-3.6$ and $\sim 2-25$ years before the explosions of the SNe, respectively; the shells were expelled $\sim 2-20$ years before the explosions of the SNe if they were powered by magnetars plus CSI.

[24]  arXiv:2001.09476 [pdf, other]

Title: The X-ray Emissivity of Low-Density Stellar Populations

Authors: C. O. Heinke (1), M. G. Ivanov (1), E. W. Koch (1), R. Andrews (1), L. Chomiuk (2), H. N. Cohn (3), S. Crothers (1), T. de Boer (4), N. Ivanova (1), A. K. H. Kong (5), N. W. C. Leigh (1,6,7), P. M. Lugger (3), L. Nelson (8), C. J. Parr (1), E. W. Rosolowsky (1), A. J. Ruiter (9), C. L. Sarazin (10), A. W. Shaw (1,11), G. R. Sivakoff (1), M. van den Berg (12) ((1) University of Alberta, (2) Michigan State University, (3) Indiana University, (4) University of Surrey, (5) National Tsing Hua University, (6) American Museum of Natural History, (7) Universidad de Concepción, (8) Bishop's University, (9) University of New South Wales, (10) University of Virginia, (11) University of Nevada, (12) Harvard-Smithsonian Center for Astrophysics)

Comments: 28 pages, 23 figures. MNRAS, in press

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

The dynamical production of low-mass X-ray binaries and brighter cataclysmic variables (CVs) in dense globular clusters is well-established. We investigate how the X-ray emissivity of fainter X-ray binaries (principally CVs and coronally active binaries) varies between different environments. We compile calculations (largely from the literature) of the X-ray emissivity of old stellar populations, including open and globular clusters and several galaxies. We investigate three literature claims of unusual X-ray sources in low-density stellar populations. We show that a suggested quiescent neutron star in the open cluster NGC 6819 is a foreground M dwarf. We show that the suggested diffuse X-ray emission from an old nova shell in the globular cluster NGC 6366 is actually a background galaxy cluster. And we show that a suggested population of quiescent X-ray binaries in the Sculptor Dwarf Galaxy is mostly (perhaps entirely) background galaxies. We find that above densities of $10^4$ M$_{\odot}$/pc$^3$, the X-ray emissivity of globular clusters increases, due to dynamical production of X-ray emitting systems. Below this density, globular clusters have lower X-ray emissivity than the other populations, and we do not see a strong dependence of X-ray emissivity due to density effects. We find significant correlations between X-ray emissivity and binary fraction, metallicity, and density. Sampling these fits via bootstrap techniques gives less significant correlations, but confirms the effect of metallicity on low-density populations, and that of density on the full globular cluster sample.

[25]  arXiv:2001.09520 [pdf, other]

Title: Characteristics of the diffuse astrophysical electron and tau neutrino flux with six years of IceCube high energy cascade data

Authors: IceCube Collaboration: M. G. Aartsen, M. Ackermann, J. Adams, J. A. Aguilar, M. Ahlers, M. Ahrens, C. Alispach, K. Andeen, T. Anderson, I. Ansseau, G. Anton, C. Argüelles, J. Auffenberg, S. Axani, P. Backes, H. Bagherpour, X. Bai, A. Balagopal V., A. Barbano, S. W. Barwick, B. Bastian, V. Baum, S. Baur, R. Bay, J. J. Beatty, K.-H. Becker, J. Becker Tjus, S. BenZvi, D. Berley, E. Bernardini, D. Z. Besson, G. Binder, D. Bindig, E. Blaufuss, S. Blot, C. Bohm, S. Böser, O. Botner, J. Böttcher, E. Bourbeau, J. Bourbeau, F. Bradascio, J. Braun, S. Bron, J. Brostean-Kaiser, A. Burgman, J. Buscher, R. S. Busse, T. Carver, C. Chen, E. Cheung, D. Chirkin, S. Choi, K. Clark, L. Classen, A. Coleman, G. H. Collin, J. M. Conrad, P. Coppin, P. Correa, D. F. Cowen, R. Cross, P. Dave, C. De Clercq, et al. (297 additional authors not shown)

Comments: 4 figures, 4 tables, includes supplementary material

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

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010 -- 2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated ($\sim 90 \%$) by electron and tau flavors. The flux, observed in the energy range from $16\,\mathrm{TeV} $ to $2.6\,\mathrm{PeV}$, is consistent with a single power-law as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be $\gamma=2.53\pm0.07$ and a flux normalization for each neutrino flavor of $\phi_{astro} = 1.66^{+0.25}_{-0.27}$ at $E_{0} = 100\, \mathrm{TeV}$. This flux of electron and tau neutrinos is in agreement with IceCube muon neutrino results and with all-neutrino flavor results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p-value $\ge 0.06$).

[26]  arXiv:2001.09537 [pdf, other]

Title: CO gas and dust outbursts from Centaur 29P/Schwassmann-Wachmann

Authors: Kacper Wierzchos, Maria Womack

Comments: Accepted for publication in The Astronomical Journal

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

29P/Schwassmann Wachmann is an unusual solar system object. Originally classified as a short-period comet, it is now known as a Centaur that recently transferred to its current orbit, and may become a Jupiter Family comet. It has exhibited a dust coma for over 90 years, and regularly undergoes significant dust outbursts. Carbon monoxide is routinely detected in high amounts and is typically assumed to play a large role in generating the quiescent dust coma and outbursts. To test this hypothesis, we completed two 3-month long observing campaigns of the CO J=2-1 rotational line using the Arizona Radio Observatory 10m Sub-millimeter Telescope during 2016 and 2018-2019, and compared the results to visible magnitudes obtained at the same time. As the Centaur approached its 2019 perihelion, the quiescent dust coma grew $\sim$45\% in brightness, while it is unclear whether the quiescent CO production rate also increased. A doubling of the CO production rate on 2016 Feb 28.6 UT did not trigger an outburst nor a rise in dust production for at least 10 days. Similarly, two dust outbursts occurred in 2018 while CO production continued at quiescent rates. Two other dust outbursts may show gas involvement. The data indicate that CO- and dust-outbursts are not always well-correlated. This may be explained if CO is not always substantially incorporated with the dust component in the nucleus, or if CO is primarily released through a porous material. Additionally, other minor volatiles or physical processes may help generate dust outbursts.

[27]  arXiv:2001.09542 [pdf, other]

Title: Machine learning applied to simulations of collisions between rotating, differentiated planets

Authors: Miles Timpe, Maria Han Veiga, Mischa Knabenhans, Joachim Stadel, Stefano Marelli

Comments: 28 pages, 8 figures. Submitted to Computational Astrophysics and Cosmology

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

In the late stages of terrestrial planet formation, pairwise collisions between planetary-sized bodies act as the fundamental agent of planet growth. These collisions can lead to either growth or disruption of the bodies involved and are largely responsible for shaping the final characteristics of the planets. Despite their critical role in planet formation, an accurate treatment of collisions has yet to be realized. While semi-analytic methods have been proposed, they remain limited to a narrow set of post-impact properties and have only achieved relatively low accuracies. However, the rise of machine learning and access to increased computing power have enabled novel data-driven approaches. In this work, we show that data-driven emulation techniques are capable of predicting the outcome of collisions with high accuracy and are generalizable to any quantifiable post-impact quantity. In particular, we focus on the dataset requirements, training pipeline, and regression performance for four distinct data-driven techniques from machine learning (ensemble methods and neural networks) and uncertainty quantification (Gaussian processes and polynomial chaos expansion). We compare these methods to existing analytic and semi-analytic methods. Such data-driven emulators are poised to replace the methods currently used in N-body simulations. This work is based on a new set of 10,700 SPH simulations of pairwise collisions between rotating, differentiated bodies at all possible mutual orientations.

[28]  arXiv:2001.09559 [pdf, ps, other]

Title: Large-scale molecular gas distribution in the M17 cloud complex: dense gas conditions of massive star formation?

Authors: Quang Nguyen-Luong, Fumitaka Nakamura, Koji Sugitani, Tomomi Shimoikura, Kazuhito Dobashi, Shinichi W. Kinoshita, Kee-Tae Kim, Hynwoo Kang, Patricio Sanhueza, Neal J. Evans II, Glenn J. White

Comments: We welcome all comments to make the paper better. Please send comments to my email. Thank you

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

The non-uniform distribution of gas and protostars in molecular clouds is caused by combinations of various physical processes that are difficult to separate. We explore this non-uniform distribution in the M17 molecular cloud complex that hosts massive star formation activity using the $^{12}$CO ($J=1-0$) and $^{13}$CO ($J=1-0$) emission lines obtained with the Nobeyama 45m telescope. Differences in clump properties such as mass, size, and gravitational boundedness reflect the different evolutionary stages of the M17-H{\scriptsize II} and M17-IRDC clouds. Clumps in the M17-H{\scriptsize II} cloud are denser, more compact, and more gravitationally bound than those in M17-IRDC. While M17-H{\scriptsize II} hosts a large fraction of very dense gas (27\%) that has column density larger than the threshold of $\sim$ 1 g cm$^{-2}$ theoretically predicted for massive star formation, this very dense gas is deficient in M17-IRDC (0.46\%). Our HCO$^+$ ($J=1-0$) and HCN ($J=1-0$) observations with the TRAO 14m telescope, {\nlqb trace all gas with column density higher than $3\times 10^{22}$ cm$^{-2}$}, confirm the deficiency of high density ($\gtrsim 10^5$ cm$^{-3}$) gas in M17-IRDC. Although M17-IRDC is massive enough to potentially form massive stars, its deficiency of very dense gas and gravitationally bound clumps can explain the current lack of massive star formation.

[29]  arXiv:2001.09562 [pdf, ps, other]

Title: The effect of CO-H2O collisions in the rotational excitation of cometary CO

Authors: A. Faure, F. Lique, J. Loreau

Comments: 8 pages, 7 figures, accepted for publication in MNRAS (January 20 2020)

Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Chemical Physics (physics.chem-ph)

We present the first accurate rate coefficients for the rotational excitation of CO by H2O in the kinetic temperature range 5-100 K. The statistical adiabatic channel method (SACM) is combined with a high-level rigid-rotor CO-H2O intermolecular potential surface. Transitions among the first 11 rotational levels of CO and the first 8 rotational levels of both para-H2O and ortho-H2O are considered. Our rate coefficients are compared to previous data from the literature and they are also incorporated in a simple non-LTE model of cometary coma including collision-induced transitions, solar radiative pumping and radiative decay. We find that the uncertainties in the collision data have significant influence on the CO population distribution for H2O densities in the range 10^3-10^8 cm^-3. We also show that the rotational distribution of H2O plays an important role in CO excitation (owing to correlated energy transfer in both CO and H2O), while the impact of the ortho-to-para ratio of H2O is found to be negligible.

[30]  arXiv:2001.09566 [pdf, other]

Title: MAGIC very large zenith angle observations of the Crab Nebula up to 100 TeV

Authors: MAGIC Collaboration: V. A. Acciari, S. Ansoldi, L. A. Antonelli, A. Arbet Engels, D. Baack, A. Babić, B. Banerjee, U. Barres de Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, L. Bellizzi, E. Bernardini, A. Berti, J. Besenrieder, W. Bhattacharyya, C. Bigongiari, A. Biland, O. Blanch, G. Bonnoli, Ž. Bošnjak, G. Busetto, R. Carosi, G. Ceribella, Y. Chai, A. Chilingaryan, S. Cikota, S. M. Colak, U. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, V. D'Elia, P. Da Vela, F. Dazzi, A. De Angelis, B. De Lotto, M. Delfino, J. Delgado, D. Depaoli, F. Di Pierro, L. Di Venere, E. Do Souto Espiñeira, D. Dominis Prester, A. Donini, D. Dorner, M. Doro, D. Elsaesser, V. Fallah Ramazani, A. Fattorini, G. Ferrara, D. Fidalgo, L. Foffano, M. V. Fonseca, L. Font, et al. (115 additional authors not shown)

Comments: 10 pages, 10 figures, accepted to A&A

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Aims: We aim to measure the Crab Nebula gamma-ray spectral energy distribution in the ~100 TeV energy domain and test the validity of existing leptonic emission models at these high energies.
Methods: We use the novel very large zenith angle observations with the MAGIC telescope system to increase the collection area above 10 TeV. We also develop an auxiliary procedure of monitoring atmospheric transmission in order to assure proper calibration of the accumulated data. This employs recording of optical images of the stellar field next to the source position, which provides a better than 10% accuracy for the transmission measurements.
Results: We demonstrate that MAGIC very large zenith angle observations yield a collection area larger than a square kilometer. In only ~56 hr of observations, we detect the gamma-ray emission from the Crab Nebula up to 100 TeV, thus providing the highest energy measurement of this source to date with Imaging Atmospheric Cherenkov Telescopes. Comparing accumulated and archival MAGIC and Fermi/LAT data with some of the existing emission models, we find that none of them provides an accurate description of the 1 GeV to 100 TeV gamma-ray signal.

[31]  arXiv:2001.09584 [pdf, other]

Title: Gravitational microlensing events from the first year of the northern Galactic plane survey by the Zwicky Transient Facility

Authors: P. Mroz, R.A. Street, E. Bachelet, E.O. Ofek, E.C. Bellm, R. Dekany, D.A. Duev, A. Gal-Yam, M.J. Graham, F.J. Masci, M. Porter, B. Rusholme, R.M. Smith, M.T. Soumagnac, J. Zolkower

Comments: 10 pages, 1 figure

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

The Zwicky Transient Facility (ZTF) is currently surveying the entire northern sky, including dense Galactic plane fields. Here, we present preliminary results of the search for gravitational microlensing events in the ZTF data collected from the beginning of the survey (March 20, 2018) through June 30, 2019.

[32]  arXiv:2001.09587 [pdf, other]

Title: The Atacama Cosmology Telescope: SZ-based masses and dust emission from IR-selected cluster candidates in the SHELA survey

Authors: Brittany J. Fuzia, Lalitwadee Kawinwanichakij, Nicola Mehrtens, Simone Aiola, Nicholas Battaglia, Robin Ciardullo, Mark Devlin, Steven L. Finkelstein, Megan Gralla, Matt Hilton, Kevin M. Huffenberger, John P. Hughes, Shardha Jogee, Felipe A. Maldonado, Lyman A. Page, Casey Papovich, Bruce Partridge, Eli Rykoff, Neelima Sehgal, Cristobal Sifon, Suzanne T. Staggs, Edward Wollack

Comments: 14 pages, 7 figures. Submitted to MNRAS

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

We examine the stacked thermal Sunyaev-Zel\text{'}dovich (SZ) signals for a sample of galaxy cluster candidates from the Spitzer-HETDEX Exploratory Large Area (SHELA) Survey, which are identified in combined optical and infrared SHELA data using the redMaPPer algorithm. We separate the clusters into three richness bins, with average photometric redshifts ranging from 0.70 to 0.80. The richest bin shows a clear temperature decrement at 148 GHz in the Atacama Cosmology Telescope data, which we attribute to the SZ effect. All richness bins show an increment at 220 GHz, which we attribute to dust emission from cluster galaxies. We correct for dust emission using stacked profiles from Herschel Stripe 82 data, and allow for synchrotron emission using stacked profiles created by binning source fluxes from NVSS data. We see dust emission in all three richness bins, but can only confidently detect the SZ decrement in the highest richness bin, finding $M_{500}$ = $8.7^{+1.7}_{-1.3} \times 10^{13} M_\odot$. Neglecting the correction for dust depresses the inferred mass by 26 percent, indicating a partial fill-in of the SZ decrement from thermal dust and synchrotron emission by the cluster member galaxies. We compare our corrected SZ masses to two redMaPPer mass--richness scaling relations and find that the SZ mass is lower than predicted by the richness. We discuss possible explanations for this discrepancy, and note that the SHELA richnesses may differ from previous richness measurements due to the inclusion of IR data in redMaPPer.

[33]  arXiv:2001.09589 [pdf, other]

Title: Local Group Analogs in $Λ$CDM cosmological simulations

Authors: Meng Zhai, Qi Guo, Gang Zhao, Qing Gu, Ang Liu

Comments: ApJ accepted

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

We use semi-analytic galaxy catalogs based on two high-resolution cosmological $N$-body simulations, Millennium-WMAP7 and Millennium-II, to investigate the formation of the Local Group (LG) analogs. Unlike previous studies, we use the observed stellar masses to select the LG member (Milky Way (MW) and M31) analogs, and then impose constrains using the observed separation, isolation, and kinematics of the two main member galaxies. By comparing radial and low-ellipticity orbits between the MW and M31, we find higher tangential velocity results in higher total mass, which are 4.4$^{+2.4}_{-1.5}\times$10$^{12}\rm M_{\odot}$ and 6.6$^{+2.7}_{-1.5}\times$10$^{12}\rm M_{\odot}$ for radial and low-ellipticity orbits. The orbits also influence the individual mass distribution of MW and M31 analogs. For radial orbits, the typical host halo masses of the MW and M31 are 1.5$^{+1.4}_{-0.7}\times$10$^{12}\rm M_{\odot}$ and 2.5$^{+1.3}_{-1.1}\times$10$^{12}\rm M_{\odot}$; for low-ellipticity orbits, the masses are 2.5$^{+2.2}_{-1.4}\times$10$^{12}\rm M_{\odot}$ and 3.8$^{+2.8}_{-1.8}\times$10$^{12} \rm M_{\odot}$. The LG is located primarily in filaments with tails extending toward higher densities up to $\delta\sim4.5$. The dark matter velocity anisotropy parameters $\beta$ of both the MW and M31 analogs are close to zero in the center, increasing to 0.2--0.3 at 50--80 kpc and decreasing slowly outward. The slope is much flatter than computed from the MW satellites, and the amplitude is smaller than traced by halo stars. Values of $\beta$ from different tracers agree at $\sim$120 kpc where $\beta \sim$ 0.2. We also find that model predictions agree broadly with observations in the radial distribution and luminosity function of satellites around the MW and M31.

[34]  arXiv:2001.09663 [pdf, other]

Title: Astrophysical Stochastic Gravitational Wave Background

Authors: José Antonio de Freitas Pacheco

Comments: Article to appear in Astronomische Nachrichten special issue (10 pages, 5 figures)

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

The stochastic gravitational wave background produced by supernovas, magnetars and merger of binaries constituted by a pair of compact objects is reviewed and updated. The merger of systems composed by two black holes dominates by far the background signal, whose amplitude in the range 10-100 Hz is above the sensitivity of the planned Einstein laser interferometer (ET). The background signal at 25 Hz estimated by the LIGO-VIRGO collaboration, based on the available merger detection data, is in good agreement with the present theoretical predictions.

[35]  arXiv:2001.09668 [pdf, other]

Title: Vortex pinning in the superfluid core of neutron stars and the rise of pulsar glitches

Authors: Aurélien Sourie, Nicolas Chamel

Comments: 5 pages, 3 figures. Accepted for publication in MNRAS Letters. Also includes Supplementary Material (2 pages, 3 figures)

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

Timing of the Crab and Vela pulsars have recently revealed very peculiar evolutions of their spin frequency during the early stage of a glitch. We show that these differences can be interpreted from the interactions between neutron superfluid vortices and proton fluxoids in the core of these neutron stars. In particular, pinning of individual vortices to fluxoids is found to have a dramatic impact on the mutual friction between the neutron superfluid and the rest of the star. The number of fluxoids attached to vortices turns out to be a key parameter governing the global dynamics of the star. These results may have implications for the interpretation of other astrophysical phenomena such as pulsar-free precession or the r-mode instability.

[36]  arXiv:2001.09680 [pdf, ps, other]

Title: Complex emission patterns: fluctuations and bistability of polar-cap potentials

Authors: P B Jones

Comments: 8 pages

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

Development of the ion-proton pulsar model extends it to the limit of large unscreened polar-cap potentials, for example, as in the Vela pulsar, in which ion charges differ only by small increments from their complete screening values. It is shown that the atomic number Z of an ion following its passage from the canonical Z_0 = 26 value through the electromagnetic shower region to the surface is not necessarily time-independent but can vary between fixed limits in an irregular or quasi-periodic way in a characteristic time of the order of 10^4 s. Thus at a certain Z the system may transition to an unstable state of higher electric potential and it is argued that this is the physical basis for mode-changes, long-term nulls, periodic or otherwise. The model requires an orientation of magnetic dipole moment relative to rotational spin giving a positive corotational charge density. Success of the model would fix the particle composition of the remaining parts of the magnetosphere, including the Y-point and is therefore relevant to X-ray and gamma-ray emission processes.

[37]  arXiv:2001.09722 [pdf, other]

Title: The lowest of the low: discovery of SN 2019gsc and the nature of faint Iax supernovae

Authors: Shubham Srivastav, Stephen J. Smartt, Giorgos Leloudas, Mark E. Huber, Ken Chambers, Daniele B. Malesani, Jens Hjorth, James H. Gillanders, A. Schultz, Stuart A. Sim, Katie Auchettl, Johan P. U. Fynbo, Christa Gall, Owen R. McBrien, Armin Rest, Ken W. Smith, Radoslaw Wojtak, David R. Young

Comments: 12 pages, 5 figures, submitted to ApJL

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

We present the discovery and optical follow-up of the faintest supernova-like transient known. The event (SN 2019gsc) was discovered in a star-forming host at 53 Mpc by ATLAS. A detailed multi-colour light curve was gathered with Pan-STARRS1 and follow-up spectroscopy was obtained with the NOT and Gemini-North. The spectra near maximum light show narrow features at low velocities of 3000 to 4000 km s$^{-1}$, similar to the extremely low luminosity SNe 2010ae and 2008ha, and the light curve displays a similar fast decline (\dmr $0.91 \pm 0.1$ mag). SNe 2010ae and 2008ha have been classified as type Iax supernovae, and together the three either make up a distinct physical class of their own or are at the extreme low luminosity end of this diverse supernova population. The bolometric light curve is consistent with a low kinetic energy of explosion ($E_{\rm k} \sim 10^{49}$ erg s$^{-1}$), a modest ejected mass ($M_{\rm ej} \sim 0.2$ \msol) and radioactive powering by $^{56}$Ni ($M_{\rm Ni} \sim 3 \times 10^{-3}$ \msol). The spectra are quite well reproduced with radiative transfer models (TARDIS) and a composition dominated by carbon, oxygen, magnesium, silicon and sulphur. Remarkably, all three of these extreme Iax events are in similar low-metallicity star-forming environments. The combination of the observational constraints for all three may be best explained by deflagrations of near $M_{\rm Ch}$ hybrid carbon-oxygen-neon white dwarfs which have short evolutionary pathways to formation.

[38]  arXiv:2001.09728 [pdf, ps, other]

Title: Bounds on Lorentz invariance violation from MAGIC observation of GRB 190114C

Authors: MAGIC Collaboration: V. A. Acciari (1), S. Ansoldi (2,3), L. A. Antonelli (4), A. Arbet Engels (5), D. Baack (6), A. Babić (7), B. Banerjee (8), U. Barres de Almeida (9), J. A. Barrio (10), J. Becerra González (1), W. Bednarek (11), L. Bellizzi (12), E. Bernardini (13,14), A. Berti (15), J. Besenrieder (16), W. Bhattacharyya (13), C. Bigongiari (4), A. Biland (5), O. Blanch (17), G. Bonnoli (12), Ž. Bošnjak (7), G. Busetto (14), R. Carosi (18), G. Ceribella (16), M. Cerruti (19), Y. Chai (16), A. Chilingarian (20), S. Cikota (7), S. M. Colak (17), U. Colin (16), E. Colombo (1), J. L. Contreras (10), J. Cortina (21), S. Covino (4), G. D'Amico (16), V. D'Elia (4), P. Da Vela (18,22), F. Dazzi (4), A. De Angelis (14), B. De Lotto (2), M. Delfino (17,23), J. Delgado (17,23), et al. (141 additional authors not shown)

Comments: 8 pages, 5 figures

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

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

[39]  arXiv:2001.09729 [pdf, other]

Title: The $a_0$ -- cosmology connection in MOND

Authors: Mordehai Milgrom

Comments: 10 pages, 4 figures, Based on a talk at `BonnGravity2019 -- The functioning of galaxies: challenges for Newtonian and Milgromian dynamics', Bonn, September 2019

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

I limelight and review a potentially crucial aspect of MOND: The near equality of the MOND acceleration constant, $a_0$ -- as deduced from local, galactic phenomena -- and cosmological parameters. To wit, $a_0\sim c H_0\sim c^2\Lambda^{1/2}\sim c^2/\ell_U$, where $H_0$ is the present value of the Hubble-Lema\^{i}tre constant, $\Lambda$ is the `cosmological constant', and $\ell_U$ is a cosmological characteristic length; e.g., the Hubble distance, or the de Sitter radius associated with $\Lambda$. In itself, this near equality has some important phenomenological consequences, such as the impossibility of black holes, and of cosmological strong lensing, in the MOND regime. More importantly perhaps, this `coincidence' may be a pointer to the `FUNDAMOND' -- the more basic theory underlying MOND phenomenology. The manners in which such a relation emerges in existing, underlying scheme of MOND are also reviewed, interlaced with examples of similar relations in other physical systems, between apparently-fundamental velocity, length, and acceleration constants. Such analogies may point the way to explanation of the MOND `coincidence'.

[40]  arXiv:2001.09739 [pdf, other]

Title: Equation of state and composition of the inner crust of an accreting neutron star: multicomponent model

Authors: Nikolay N. Shchechilin, Andrey I. Chugunov

Comments: 5 pages, 3 figures, published in proceedings of the International Conference PhysicA.Spb/2019, St. Petersburg, October 22-24, 2019

Journal-ref: J. Phys.: Conf. Ser., 1400 (2019), 022016

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

Correct interpretation of X-ray observations of transiently accreting neutron stars requires modeling of nuclear-physical processes in these objects. We consider a chain of nuclear reactions that drives the crust composition in an accreting neutron star and heats up the star. We constructed multicomponent approach with the kinetics of nuclear reactions described in simplified stepwise manner. The redistribution of nucleons between nuclei by emission and capture of neutrons is shown to significantly affect the nuclear reaction chains and the composition of the inner crust. In particular, even if the outer crust has one-component composition, the appearance of free neutrons in the inner crust leads to branching of reaction chains and formation of the multicomponent composition. We apply the compressible liquid drop nuclear model, which includes effects of free neutrons on nuclear energies. It allows us to calculate the composition, the heating profile and the equation of state of matter up to densities \rho ~ 2 \times 10^{13} g cm^{-3}.

[41]  arXiv:2001.09776 [pdf, other]

Title: ALMA reveals a large structured disk and nested rotating outflows in DG Tau B

Authors: A. de Valon, C. Dougados, S. Cabrit, F. Louvet, L. A. Zapata, D. Mardones

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

We present Atacama Large Millimeter Array (ALMA) Band 6 observations at 14-20 au spatial resolution of the disk and CO(2-1) outflow around the Class I protostar DG Tau B in Taurus. The disk is very large, both in dust continuum (R$_{\rm eff,95\%}$=174 au) and CO (R$_{CO}$=700 au). It shows Keplerian rotation around a 1.1$\pm$0.2 M$_{\odot}$ central star and two dust emission bumps at $r$ = 62 and 135 au. These results confirm that large structured disks can form at an early stage where residual infall is still ongoing. The redshifted CO outflow at high velocity shows a striking hollow cone morphology out to 3000 au with a shear-like velocity structure within the cone walls. These walls coincide with the scattered light cavity, and they appear to be rooted within $<$ 60 au in the disk. We confirm their global average rotation in the same sense as the disk, with a specific angular momentum $\simeq$ 65 au \kms. The mass-flux rate of 1.7-2.9 $\times$ 10$^{-7}$M$_{\odot}$ yr$^{-1}$ is 35$\pm$10 times that in the atomic jet. We also detect a wider and slower outflow component surrounding this inner conical flow, which also rotates in the same direction as the disk. Our ALMA observations therefore demonstrate that the inner cone walls, and the associated scattered light cavity, do not trace the interface with infalling material, which is shown to be confined to much wider angles ($> 70^{\circ}$). The properties of the conical walls are suggestive of the interaction between an episodic inner jet or wind with an outer disk wind, or of a massive disk wind originating from 2-5 au. However, further modeling is required to establish their origin. In either case, such massive outflow may significantly affect the disk structure and evolution.

[42]  arXiv:2001.09801 [pdf, ps, other]

Title: Secular evolution of close in planets: the effects of general relativity

Authors: Francesco Marzari, Makiko Nagasawa

Comments: Accepted for publication on MNRAS

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

Pairs of planets in a system may end up close to their host star on eccentric orbits as a consequence of planet planet scattering, Kozai or secular migration. In this scenario, general relativity and secular perturbations have comparable timescales and may interfere with each other with relevant effects on the eccentricity and pericenter evolution of the two planets. We explore, both analytically and via numerical integration, how the secular evolution is changed by general relativity for a wide range of different initial conditions. We find that when the faster secular frequency approaches the general relativity precession rate, which tipically occurs when the outer planet moves away from the inner one, it relaxes to it and a significant damping of the proper eccentricity of the inner planet occurs. The proper eccentricity of the outer planet is reduced as well due to the changes in the secular interaction of the bodies. The lowering of the peak eccentricities of the two planets during their secular evolution has important implications on their stability. A significant number of two planet systems, otherwise chaotic because of the mutual secular perturbations, are found stable when general relativity is included.

[43]  arXiv:2001.09829 [pdf, other]

Title: Common-Envelope Episodes that lead to Double Neutron Star formation

Authors: Alejandro Vigna-Gómez, Morgan MacLeod, Coenraad J. Neijssel, Floor S. Broekgaarden, Stephen Justham, George Howitt, Selma E. de Mink, Ilya Mandel

Comments: 20 pages, 9 figures, submitted version

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

Close Double Neutron Stars (DNSs) have been observed as Galactic radio pulsars, while their mergers have been detected as gamma-ray bursts and gravitational-wave sources. They are believed to have experienced at least one common-envelope episode (CEE) during their evolution prior to DNS formation. In the last decades there have been numerous efforts to understand the details of the common-envelope phase, but its computational modelling remains challenging. We present and discuss the properties of the donor and the binary at the onset of the Roche-lobe overflow (RLOF) leading to these CEEs as predicted by rapid binary population synthesis models. These properties can be used as initial conditions for detailed simulations of the common-envelope phase. There are three distinctive populations, classified by the evolutionary stage of the donor at the moment of the onset of the RLOF: giant donors with fully-convective envelopes, cool donors with partially-convective envelopes, and hot donors with radiative envelopes. We also estimate that, for standard assumptions, tides would not circularise a large fraction of these systems by the onset of RLOF. This makes the study and understanding of eccentric mass transferring systems relevant for DNS populations.

[44]  arXiv:2001.09835 [pdf, other]

Title: Photolysis-induced scrambling of PAHs as a mechanism for deuterium storage

Authors: S.D. Wiersma, A. Candian, J.M. Bakker, G. Berden, J. Oomens, W-J. Buma, A. Petrignani

Comments: 13 pages, 5 figures. Abstract abridged to meet ArXiv size limit. Accepted for publications in A&A

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

Aim. We investigate the role of PAHs as a sink for deuterium in the interstellar medium and study UV photolysis as a potential process in the variations of the deuterium fractionation in the ISM. Methods. The UV photo-induced fragmentation of various isotopologues of D-enriched, protonated anthracene and phenanthrene ions was recorded in a FTICR mass spectrometer. IRMPD spectroscopy using FELIX provided the IR spectra that were compared to DFT vibrational spectra; reaction barriers and rates were also calculated and related to the product abundances. Results. The mass spectra for both UV and IRMPD photolysis show the loss of H from [D-C$_{14}$H$_{10}$]$^+$, whereas [H-C$_{14}$D$_{10}$]$^+$ shows a strong preference for D loss. Calculations reveal facile 1,2-H and -D shift reactions, with barriers lower than the energy supplied by the photo-excitation process. Together with confirmation of the ground-state structures via the IR spectra, we determined that the photolytic processes in the 2 PAHs are largely governed by scrambling where the H and the D atoms relocate between different peripheral C atoms. The $\sim$0.1 eV difference in zero-point energy between C-H and C-D bonds ultimately leads to faster H scrambling than D scrambling, and increased H atom loss compared to D. Conclusion. Scrambling is common in PAH cations under UV radiation. Upon photoexcitation of deuterium-enriched PAHs, the scrambling results in a higher probability for the aliphatic D atom to migrate to an aromatic site, protecting it from elimination. This could lead to increased deuteration as a PAH moves towards more exposed interstellar environments. Also, large, compact PAHs with an aliphatic C-HD group on solo sites might be responsible for the majority of aliphatic C-D stretching bands seen in astronomical spectra.

[45]  arXiv:2001.09839 [pdf, other]

Title: Supercatastrophic disruption of asteroids in the context of SOHO comet, fireball and meteor observations

Authors: Paul Wiegert, Peter Brown, Petr Pokorný, Quanzhi Ye, Cole Gregg, Karina Lenartowicz, Zbigniew Krzeminski, David Clark

Comments: 20 pages, 9 figures, accepted by the Astronomical Journal

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

Granvik et al. (2016) report an absence of asteroids on orbits with perihelia near the Sun that they attribute to the 'supercatastrophic disruption' of these bodies. Here we investigate whether there is evidence for this process among other bodies with similarly low perihelia: near-Earth asteroids, SOHO comets, as well as meter-sized and millimeter-sized meteoroids. We determine no known near-Earth asteroids have past (last 10^4 years) histories residing significantly inside the Granvik et al. (2016) limit, indirectly supporting the disruption hypothesis. The exception is asteroid (467372) 2004 LG which spent 2500 years within this limit, and thus presents a challenge to that theory. Phaethon has a perihelion distance hovering just above the limit and may be undergoing slow disruption, which may be the source of its dust complex. We find that the rate at which ungrouped SOHO comets are observed is consistent with expected rates for the injection of small (25 m) class asteroids into the near-Sun region and suggest that this fraction of the SOHO-observed comet population may in fact be asteroidal in origin. We also find that there is an absence of meter-sized bodies with near-Sun perihelia but an excess of millimeter-sized meteoroids. This implies that if near-Sun asteroids disrupt, they do not simply fragment into meter-sized chunks but disintegrate ultimately into millimeter-sized particles. We propose that the disruption of near-Sun asteroids as well as the anomalous brightening and destruction processes that affect SOHO comets occur through meteoroid erosion, that is, the removal of material through impacts by high-speed near-Sun meteoroids.

[46]  arXiv:2001.09851 [pdf, other]

Title: Linking extended and plateau emissions of short gamma-ray bursts

Authors: Tatsuya Matsumoto, Shigeo S. Kimura, Kohta Murase, Peter Mészáros

Comments: 10 pages, 4 figures, 3 tables, submitted to MNRAS, comments welcome!!!

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

Some short gamma-ray bursts (SGRBs) show a longer lasting emission phase, called extended emission (EE) lasting $\sim 10^{2-3}\,\rm s$, as well as a plateau emission (PE) lasting $\sim10^{4-5}\,\rm s$. While a long-lasting activity of the central engines is a promising explanation for powering both emissions, their physical origin and their emission mechanisms are still uncertain. In this work, we study the properties of the EEs and their connection with the PEs. First, we constrain the minimal Lorentz factor $\Gamma$ of the outflows powering EEs, using compactness arguments and find that the outflows should be relativistic, $\Gamma\gtrsim10$. We propose a consistent scenario for the PEs, where the outflow eventually catches up with the jet responsible for the prompt emission, injecting energy into the forward shock formed by the prior jet, which naturally results in a PE. We also derive the radiation efficiency of EEs and the Lorentz factor of the outflow within our scenario for 10 well-observed SGRBs accompanied by both EE and PE. The efficiency has an average value of $\sim3\,\%$ but shows a broad distribution ranging from $\sim0.01$ to $\sim100\%$. The Lorentz factor is $\sim20-30$, consistent with the compactness arguments. These results suggest that EEs are produced by a slower outflow via more inefficient emission than the faster outflow which causes the prompt emission with a high radiation efficiency.

[47]  arXiv:2001.09871 [pdf, ps, other]

Title: Chandra measurements of the proper motion of the $γ$-ray pulsar J0633+0632

Authors: Andrey Danilenko, Anna Karpova, Yury Shibanov

Comments: 4 pages, 2 figures and 2 tables

Journal-ref: 2019, JPhCS, 022017, JPhCS1400

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

We measured the proper motion of a $\gamma$-ray radio-quiet pulsar J0633+0632 using Chandra observations performed in 2009 and 2017. The measured proper motion is $53\pm15$~mas~yr$^{-1}$. We found that the proper motion direction does not follow the extension of the J0633+0632 pulsar wind nebula. The J0633+0632 pulsar wind nebula therefore can be a jet-like feature or a misaligned outflow. We also discuss a possible birth cite of the pulsar.

[48]  arXiv:2001.09893 [pdf]

Title: Alternative Models of Zebra Patterns in the Event on June 21, 2011

Authors: L.V. Yasnov, G.P. Chernov

Comments: 19 pages, 5 figures, accepted

Journal-ref: Solar Physics, 2020

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

The analysis of the spectral characteristics of the burst radio emission on June 21, 2011 was carried out on the basis of an improved methodology for determining harmonic numbers for the corresponding stripes of the zebra structure. By using the parameters of the zebra structure in the time frequency spectrum and basing on the double plasma resonance model, the magnetic field and its dynamics, electron density, and the time variation of the distance between the stripes with harmonics s = 55 and 56 and adjacent stripes near the frequency 183 MHz have been determined in the burst generation region. The relationships between the scale characteristics of the field and the density along and across the axis of the power tube and their dependence on time have been also determined. The field obtained (1.5 G for the first harmonic and 0.75 G for the second harmonic of the plasma frequency) turned out to be so small that, firstly, it fails to explain the dynamic features of the spectrum based on MHD waves, and secondly, it results in large values for plasma betta (>1). Other possible difficulties of the generation mechanism of bursts with zebra pattern based on the double plasma resonance are also noted. Another possible mechanism, with whistlers explains qualitatively the main observational characteristics of this zebra. The magnetic field required in this case is about 4.5 G, and the plasma betta is 0.14, which fully corresponds to the coronal conditions.

[49]  arXiv:2001.09903 [pdf, ps, other]

Title: The connection between the UV/optical and X-ray emission in the neutron star low-mass X-ray binary Aql X-1

Authors: E. López-Navas, N. Degenaar, A.S. Parikh, J.V. Hernández Santisteban, J. van den Eijnden

Comments: 11 pages, 6 figures. Accepted in MNRAS

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

Accreting neutron stars and black holes in low-mass X-ray binaries (LMXBs) radiate across the electromagnetic spectrum. Linking the emission produced at different wavelengths can provide valuable information about the accretion process and any associated outflows. In this work, we study simultaneous X-ray and UV/optical observations of the neutron star LMXB \source, obtained with the Neil Gehrels Swift Observatory during its 2013, 2014 and 2016 accretion outbursts. We find that the UV/optical and X-ray emission are strongly correlated during all three outbursts. For the 2013 and 2014 episodes, which had the best Swift sampling, we find that the correlation between the UV/optical and X-ray fluxes is significantly steeper during the decay (soft state) of the outburst than during the rise (hard-to-soft state). We observe an UV/optical hysteresis behaviour that is likely linked to the commonly known X-ray spectral hysteresis pattern. For the decays of the three outbursts we obtain a correlation index that cannot be directly explained by any single model. We suspect that this is a result of multiple emission processes contributing to the UV/optical emission, but we discuss alternative explanations. Based on these correlations, we discuss which mechanisms are likely dominating the UV/optical emission of Aql X-1.

[50]  arXiv:2001.09905 [pdf, other]

Title: Search for the optical counterpart of the GW170814 gravitationalwave event with the VLT Survey Telescope

Authors: A. Grado, E. Cappellaro, S. Covino, F. Getman, G. Greco, L. Limatola, S. Yang, L. Amati, S. Benetti, M. Branchesi, E. Brocato, M. Botticella, S. Campana, M. Cantiello, M. Dadina, F. D'Ammando, G. De Cesare, V. D'Elia, M. Della Valle, E. Iodice, G. Longo, M. Mapelli, N. Masetti, L. Nicastro, E. Palazzi, A. Possenti, M. Radovich, A. Rossi, R. Salvaterra, L. Stella, G. Stratta, V. Testa, L. Tomasella

Comments: 24 pages, 7 figures, MNRAS, 492, 1731 (2020)

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

We report on the search for the optical counterpart of the gravitational event GW170814, which was carried out with the VLT Survey Telescope (VST) by the GRAvitational Wave Inaf TeAm (GRAWITA). Observations started 17.5 hours after the LIGO/Virgo alert and we covered an area of 99 deg$^2$ that encloses $\sim 77\%$ and $\sim 59\%$ of the initial and refined localization probability regions, respectively. A total of six epochs were secured over nearly two months. The survey reached an average limiting magnitude of 22 AB mag in the $r-$band. After assuming the model described in Perna et al. 2019 that derives as possible optical counterpart of a BBH event a transient source declining in about one day, we have computed a survey efficiency of about $5\%$. This paper describes the VST observational strategy and the results obtained by our analysis pipelines developed to search for optical transients in multi-epoch images. We report the catalogue of the candidates with possible identifications based on light-curve fitting. We have identified two dozens of SNe, nine AGNs, one QSO. Nineteen transients characterized by a single detection were not classified. We have restricted our analysis only to the candidates that fall into the refined localization map. None out of 39 left candidates could be positively associated with GW170814. This result implies that the possible emission of optical radiation from a BBH merger had to be fainter than r $\sim$ 22 ($L_{optical}$ $\sim$ $1.4 \times 10^{42}$ erg/s) on a time interval ranging from a few hours up to two months after the GW event.

[51]  arXiv:2001.09933 [pdf, other]

Title: Cosmic-ray interactions with the Sun using the FLUKA code

Authors: M. N. Mazziotta, P. De La Torre Luque, L. Di Venere, A. Ferrari, A. Fassò, F. Loparco, P. R. Sala, D.Serini

Comments: 12 pages, 12 figures, comments welcome

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

The interactions of cosmic rays with the solar atmosphere produce secondary particle which can reach the Earth. In this work we present a comprehensive calculation of the yields of secondary particles as gamma-rays, electrons, positrons, neutrons and neutrinos performed with the FLUKA code. We also estimate the intensity at the Sun and the fluxes at the Earth of these secondary particles by folding their yields with the intensities of cosmic rays impinging on the solar surface. The results are sensitive on the assumptions on the magnetic field nearby the Sun and to the cosmic-ray transport in the magnetic field in the inner solar system.

[52]  arXiv:2001.09959 [pdf, other]

Title: Superfluidity in Disordered Neutron Stars Crusts

Authors: J. A. Sauls, N. Chamel, M. A. Alpar

Comments: 6 pages, 5 figures

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Superconductivity (cond-mat.supr-con); Nuclear Theory (nucl-th)

Nonequilibrium conditions imposed by neutrino cooling through the liquid-solid transition lead to disorder in the solid crust of neutron stars. Disorder reduces the superfluid fraction, $\rho_s/\rho$, at densities above that of neutron drip, $\rho_d \approx 4\times 10^{11}\,g/cm^3$. For an amorphous solid crust the suppression of $\rho_s$ is small, except in the highest density regions of the crust. In contrast to the strong reduction in neutron conduction predicted for coherent Bragg scattering in a crystalline crust, the disordered solid crust supports sufficient neutron superfluid density to account for pulsar glitches.

[53]  arXiv:2001.09984 [pdf, ps, other]

Title: Universal bolometric corrections for AGN over 7 luminosity decades

Authors: F. Duras, A. Bongiorno, F. Ricci, E. Piconcelli, F. Shankar, E. Lusso, S. Bianchi, F. Fiore, R. Maiolino, A. Marconi, F. Onori, E. Sani, R. Schneider, C. Vignali, F. La Franca

Comments: Accepted for publication in A&A

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

The AGN bolometric correction is a key element to understand BH demographics and compute accurate BH accretion histories from AGN luminosities. However, current estimates still differ from each other by up to a factor of two to three, and rely on extrapolations at the lowest and highest luminosities. Here we revisit this fundamental issue presenting general hard X-ray ($K_{X}$) and optical ($K_{O}$) bolometric corrections, computed combining several AGN samples spanning the widest (about 7 dex) luminosity range ever used for this kind of studies. We analysed a total of $\sim 1000$ type 1 and type 2 AGN for which a dedicated SED-fitting has been carried out. We provide a bolometric correction separately for type 1 and type 2 AGN; the two bolometric corrections results to be in agreement in the overlapping luminosity range and therefore, for the first time, a universal bolometric correction for the whole AGN sample (both type 1 and type 2) has been computed. We found that $K_{X}$ is fairly constant at $log(L_{BOL}/L_{\odot}) < 11$, while it increases up to about one order of magnitude at $log(L_{BOL}/L_{\odot}) \sim 14.5$. A similar increasing trend has been observed when its dependence on either the Eddington ratio or the BH mass is considered, while no dependence on redshift up to $z\sim3.5$ has been found. On the contrary, the optical bolometric correction appears to be fairly constant (i.e. $K_{O} \sim 5$) whatever is the independent variable. We also verified that our bolometric corrections correctly predict the AGN bolometric luminosity functions. According to this analysis, our bolometric corrections can be applied to the whole AGN population in a wide range of luminosity and redshift.

[54]  arXiv:2001.09985 [pdf, other]

Title: Contribution of pulsars to cosmic-ray positrons in light of recent observation of inverse-Compton halos

Authors: Silvia Manconi, Mattia Di Mauro, Fiorenza Donato

Comments: 10 pages, 7 figures

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

The hypothesis that pulsar wind nebulae (PWNe) can significantly contribute to the excess of the positron ($e^+$) cosmic-ray flux has been consolidated after the observation of a $\gamma$-ray emission at TeV energies of a few degree size around Geminga and Monogem PWNe, and at GeV energies for Geminga at a much larger extension. The $\gamma$-ray halos around these PWNe are interpreted as due to electrons ($e^-$) and $e^+$ accelerated and escaped by their PWNe, and inverse Compton scattering low-energy photons of the interstellar radiation fields. The extension of these halos suggests that the diffusion around these PWNe is suppressed by two orders of magnitude with respect to the average in the Galaxy. We implement a two-zone diffusion model for the propagation of $e^+$ accelerated by the Galactic population of PWNe. We consider pulsars from the ATNF catalog and build up simulations of the PWN Galactic population. In both scenarios, we find that within a two-zone diffusion model, the total contribution from PWNe and secondary $e^+$ is at the level of AMS-02 data, for an efficiency of conversion of the pulsar spin down energy in $e^\pm$ of $\eta\sim0.1$. For the simulated PWNe, a $1\sigma$ uncertainty band is determined, which is of at least one order of magnitude from 10 GeV up to few TeV. The hint for a decreasing $e^+$ flux at TeV energies is found, even if it is strongly connected to the chosen value of the radius of the low diffusion bubble around each source.

Cross-lists for Tue, 28 Jan 20

[55]  arXiv:2001.08887 (cross-list from physics.ins-det) [pdf, ps, other]

Title: Thermal Kinetic Inductance Detectors for Millimeter-Wave Astrophysics

Authors: Albert Wandui, Jamie Bock, Clifford Frez, Matthew Hollister, Lorenzo Minutolo, Hien Nguyen, Bryan Steinbach, Anthony Turner, Jonas Zmuidzinas, Roger O'Brient

Comments: 15 pages, 12 figures

Subjects: Instrumentation and Detectors (physics.ins-det); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Thermal Kinetic Inductance Detectors (TKIDs) combine the excellent noise performance of traditional bolometers with a radio frequency (RF) multiplexing architecture that enables the large detector counts needed for the next generation of millimeter-wave instruments. Here we present dark prototype TKID pixels that demonstrate a noise equivalent power NEP = $2 \times 10^{-17} \mathrm{W}/\mathrm{\sqrt{Hz}} $ with a $1/f$ knee at 0.1 Hz, suitable for background-limited noise performance at 150 GHz from a ground-based site. We discuss the optimizations in the device design and fabrication techniques to realize optimal electrical performance and high quality factors at a bath temperature of 250 mK.

[56]  arXiv:2001.09231 (cross-list from physics.space-ph) [pdf, other]

Title: Electron energy partition across interplanetary shocks: III. Analysis

Authors: L.B. Wilson III, Li-Jen Chen, Shan Wang, Steven J. Schwartz, Drew L. Turner, Michael L. Stevens, Justin C. Kasper, Adnane Osmane, Damiano Caprioli, Stuart D. Bale, Marc P. Pulupa, Chadi S. Salem, Katherine A. Goodrich

Comments: 30 pages, 10 figures, 3 tables, to be submitted to Astrophys. J

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

Analysis of model fit results of 15,210 electron velocity distribution functions (VDFs), observed within $\pm$2 hours of 52 interplanetary (IP) shocks by the Wind spacecraft near 1 AU, is presented as the third and final part on electron VDFs near IP shocks. The core electrons and protons dominate in the magnitude and change in the partial-to-total thermal pressure ratio, with the core electrons often gaining as much or more than the protons. Only a moderate positive correlation is observed between the electron temperature and the kinetic energy change across the shock, while weaker, if any, correlations were found with any other macroscopic shock parameter. No VDF parameter correlated with the shock normal angle. The electron VDF evolves from a narrowly peaked core with flaring suprathermal tails in the upstream to either a slightly hotter core with steeper tails or much hotter flattop core with even steeper tails downstream of the weaker and strongest shocks, respectively. Both quasi-static and fluctuating fields are examined as possible mechanisms modifying the VDF but neither is sufficient alone. For instance, flattop VDFs can be generated by nonlinear ion acoustic wave stochastic acceleration (i.e., inelastic collisions) while other work suggested they result from the combination of quasi-static and fluctuating fields. This three-part study shows that not only are these systems not thermodynamic in nature, even kinetic models may require modification to include things like inelastic collision operators to properly model electron VDF evolution across shocks or in the solar wind.

[57]  arXiv:2001.09378 (cross-list from gr-qc) [pdf, other]

Title: Karmarkar scalar condition

Authors: J. Ospino, L.A. Nunez

Comments: 13 pages, 1 figures. arXiv admin note: text overlap with arXiv:1810.03059

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

In this work we present the Karmarkar condition in terms of the structure scalars obtained from the orthogonal decomposition of the Riemann tensor. This the new expression becomes an algebraic relation among the physical variables, and not a differential equation between the metric coefficients. By using the Karmarkar scalar condition we implement a method to obtain all possible embedding class I static spherical solutions, provided the energy density profile is given. We also analyse the dynamic adiabatic case and show the incompatibility of the Kamarkar condition with several commonly assumed simplifications to the study of gravitational collapse. Finally, we consider the dissipative dynamic Karmarkar collapse and find a new solution family.

[58]  arXiv:2001.09553 (cross-list from gr-qc) [pdf, other]

Title: Quantum Black Holes in the Sky

Authors: Jahed Abedi (AEI, Hanover), Niayesh Afshordi (UW/PI), Naritaka Oshita (PI), Qingwen Wang (UW/PI)

Comments: 78 pages, 42 figures, Invited review article for the special issue of the journal "Universe" on "Probing new physics with black holes", Comment are very welcome!

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

Black Holes are possibly the most enigmatic objects in our Universe. From their detection in gravitational waves upon their mergers, to their snapshot eating at the centres of galaxies, black hole astrophysics has undergone an observational renaissance in the past 4 years. Nevertheless, they remain active playgrounds for strong gravity and quantum effects, where novel aspects of the elusive theory of quantum gravity may be hard at work. In this review article, we provide an overview of the strong motivations for why "Quantum Black Holes" may be radically different from their classical counterparts in Einstein's General Relativity. We then discuss the observational signatures of quantum black holes, focusing on gravitational wave echoes as smoking guns for quantum horizons (or exotic compact objects), which have led to significant recent excitement and activity. We review the theoretical underpinning of gravitational wave echoes and critically examine the seemingly contradictory observational claims regarding their (non-)existence. Finally, we discuss the future theoretical and observational landscape for unraveling the "Quantum Black Holes in the Sky".

[59]  arXiv:2001.09669 (cross-list from gr-qc) [pdf, other]

Title: Non-linear evolutions of magnetised thick discs around black holes: dependence on the initial data

Authors: Alejandro Cruz-Osorio, Sergio Gimeno-Soler, José A. Font

Comments: 13 pages, 11 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society

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

We build equilibrium solutions of magnetised thick discs around a highly spinning Kerr black hole and evolve these initial data up to a final time of about 100 orbital periods. The numerical simulations reported in this paper solve the general relativistic magnetohydrodynamics equations using the BHAC code and are performed in axisymmetry. Our study assumes non-self-gravitating, polytropic, constant angular momentum discs endowed with a purely toroidal magnetic field. In order to build the initial data we consider three approaches, two of which incorporate the magnetic field in a self-consistent way and a third approach in which the magnetic field is included as a perturbation on to an otherwise purely hydrodynamical solution. To test the dependence of the evolution on the initial data, we explore four representative values of the magnetisation parameter spanning from almost hydrodynamical discs to very strongly magnetised tori. The initial data are perturbed to allow for mass and angular momentum accretion on to the black hole. Notable differences are found in the long-term evolutions of the initial data. In particular, our study reveals that highly magnetised discs are unstable, and hence prone to be fully accreted and expelled, unless the magnetic field is incorporated into the initial data in a self-consistent way.

[60]  arXiv:2001.09757 (cross-list from physics.ao-ph) [pdf]

Title: Spatial Analysis of Seasonal Precipitation over Iran: Co-Variation with Climate Indices

Authors: Majid Dehghani, Somayeh Salehi, Amir Mosavi, Narjes Nabipour, Shahaboddin Shamshirband, Pedram Ghamisi

Comments: 25 pages, 10 figures

Subjects: Atmospheric and Oceanic Physics (physics.ao-ph); Earth and Planetary Astrophysics (astro-ph.EP)

Temporary changes in precipitation may lead to sustained and severe drought or massive floods in different parts of the world. Knowing variation in precipitation can effectively help the water resources decision-makers in water resources management. Large-scale circulation drivers have a considerable impact on precipitation in different parts of the world. In this research, the impact of El Ni\~no-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and North Atlantic Oscillation (NAO) on seasonal precipitation over Iran was investigated. For this purpose, 103 synoptic stations with at least 30 years of data were utilized. The Spearman correlation coefficient between the indices in the previous 12 months with seasonal precipitation was calculated, and the meaningful correlations were extracted. Then the month in which each of these indices has the highest correlation with seasonal precipitation was determined. Finally, the overall amount of increase or decrease in seasonal precipitation due to each of these indices was calculated. Results indicate the Southern Oscillation Index (SOI), NAO, and PDO have the most impact on seasonal precipitation, respectively. Also, these indices have the highest impact on the precipitation in winter, autumn, spring, and summer, respectively. SOI has a diverse impact on winter precipitation compared to the PDO and NAO, while in the other seasons, each index has its special impact on seasonal precipitation. Generally, all indices in different phases may decrease the seasonal precipitation up to 100%. However, the seasonal precipitation may increase more than 100% in different seasons due to the impact of these indices. The results of this study can be used effectively in water resources management and especially in dam operation.

[61]  arXiv:2001.09759 (cross-list from physics.ao-ph) [pdf]

Title: Gamma Ray Flashes Produced by Lightning Observed at Ground Level by TETRA-II

Authors: D. J. Pleshinger (1), S. T. Alnussirat (1), J. Arias (2), S. Bai (3), Y. Banadaki (3), M. L. Cherry (1), J. H. Hoffman (1), E. Khosravi (3), M. D. Legault (4), R. Rodriguez (5), D. Smith (1), D. Smith (6), E. del Toro (5), J. C. Trepanier (6), A. Sunda-Meya (7) ((1) Louisiana State Univ. Dept. of Physics & Astronomy, (2) Centro Nacional de Metrologiá de Panamá, (3) Southern Univ., (4) Univ. of Puerto Rico at Bayamón, (5) Univ. of Puerto Rico at Utuado, (6) Louisiana State Univ. Dept. of Geography & Anthropology,(7) Xavier Univ. of New Orleans)

Comments: 10 pages, 9 figures

Journal-ref: J. Geophys. Res.-Space Phys. 124, 9229 (2019)

Subjects: Atmospheric and Oceanic Physics (physics.ao-ph); Earth and Planetary Astrophysics (astro-ph.EP); High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM); Instrumentation and Detectors (physics.ins-det)

In its first 2 years of operation, the ground-based Terrestrial gamma ray flash and Energetic Thunderstorm Rooftop Array(TETRA)-II array of gamma ray detectors has recorded 22 bursts of gamma rays of millisecond-scale duration associated with lightning. In this study, we present the TETRA-II observations detected at the three TETRA-II ground-level sites in Louisiana, Puerto Rico, and Panama together with the simultaneous radio frequency signals from the VAISALA Global Lightning Data set, VAISALA National Lightning Detection Network, Earth Networks Total Lightning Network, and World Wide Lightning Location Network. The relative timing between the gamma ray events and the lightning activity is a key parameter for understanding the production mechanism(s) of the bursts. The gamma ray time profiles and their correlation with radio sferics suggest that the gamma ray events are initiated by lightning leader activity and are produced near the last stage of lightning leader channel development prior to the lightning return stroke.

[62]  arXiv:2001.09885 (cross-list from gr-qc) [pdf, other]

Title: Understanding the phenomenology of interacting dark energy scenarios and their theoretical bounds

Authors: Supriya Pan, Jaume de Haro, Weiqiang Yang, Jaume Amorós

Comments: 15 pages, 8 figures; comments are welcome

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

Non-gravitational interaction between dark matter and dark energy has been considered in a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. The interaction rate is assumed to be linear in the energy densities of dark matter and dark energy, and additionally, it is proportional to the Hubble rate of the background universe. This kind of interaction model leads to an autonomous linear dynamical system, and depending on the coupling parameters, could be solved analytically by calculating the exponential of the matrix, defining the system. And such interaction rate, as we explicitly present here, has a deep connection with some well known cosmological theories. We investigate the theoretical bounds on the coupling parameters in order that the energy densities of the dark sector remain positive throughout the evolution of the universe and asymptotically converge to zero at very late times. Our analyses also reveal that such linear interacting models may encounter with finite time future singularities depending on the coupling parameters and the dark energy state parameter.

[63]  arXiv:2001.09889 (cross-list from gr-qc) [pdf, ps, other]

Title: Redshift and gauge choice

Authors: Harald Skarke

Comments: 12 pages

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

We show that a specific gauge choice comes extremely close to defining a frame whose preferred observers see a dipole-free CMB. In this gauge the metric is the product of a scale factor depending on all spacetime coordinates, and a metric featuring an expansion-free geodesic timelike vector field. This setup facilitates the computation of redshift and other distance measures and explains why we can have a highly isotropic CMB despite large inhomogeneities.

Replacements for Tue, 28 Jan 20

[64]  arXiv:1211.5415 (replaced) [pdf, ps, other]

Title: Non-Maxwellian and non-chi-square distributions for a system with limited number of entities

Authors: Jae Wan Shim

Comments: 13 pages, 6 figures

Subjects: Mathematical Physics (math-ph); Instrumentation and Methods for Astrophysics (astro-ph.IM); Accelerator Physics (physics.acc-ph)

[65]  arXiv:1605.05663 (replaced) [pdf]

Title: Reviewing METI: A Critical Analysis of the Arguments

Authors: John Gertz

Comments: 8 pages, 0 figures, Published in JBIS Vol. 69, 2016

Subjects: Popular Physics (physics.pop-ph); Instrumentation and Methods for Astrophysics (astro-ph.IM)

[66]  arXiv:1701.08422 (replaced) [pdf]

Title: Post-Detection SETI Protocols & METI: The Time Has Come To Regulate Them Both

Authors: John Gertz

Comments: 20 pages, 0 figures, Published in JBIS Vol. 69 No. 8 August 2016

Journal-ref: JBIS Vol. 69 No. 8 August 2016

Subjects: Popular Physics (physics.pop-ph); Earth and Planetary Astrophysics (astro-ph.EP)

[67]  arXiv:1805.07158 (replaced) [pdf, ps, other]

Title: New classification parameter of solar flares based on the maximum flux in soft X-rays and on duration of flare

Authors: Elena Bruevich

Comments: 29 pages, 17 figures

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

[68]  arXiv:1904.02901 (replaced) [pdf, other]

Title: The POLARBEAR Fourier Transform Spectrometer Calibrator and Spectroscopic Characterization of the POLARBEAR Instrument

Authors: Frederick Matsuda, Lindsay Lowry, Aritoki Suzuki, Mario Aguilar Faundez, Kam Arnold, Darcy Barron, Federico Bianchini, Kolen Cheung, Yuji Chinone, Tucker Elleflot, Giulio Fabbian, Neil Goeckner-Wald, Masaya Hasegawa, Daisuke Kaneko, Nobuhiko Katayama, Brian Keating, Adrian Lee, Martin Navaroli, Haruki Nishino, Hans Paar, Giuseppe Puglisi, Paul Richards, Joseph Seibert, Praween Siritanasak, Osamu Tajima, Sayuri Takatori, Calvin Tsai, Ben Westbrook

Journal-ref: Review of Scientific Instruments 90, 115115 (2019)

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

[69]  arXiv:1905.00464 (replaced) [pdf, other]

Title: On Reflectivity of Quantum Black Hole Horizons

Authors: Naritaka Oshita, Qingwen Wang, Niayesh Afshordi

Comments: 15 pages, 5 figures, appendixes added

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

[70]  arXiv:1905.04268 (replaced) [pdf, ps, other]

Title: BlackHawk: A public code for calculating the Hawking evaporation spectra of any black hole distribution

Authors: Alexandre Arbey, Jérémy Auffinger

Comments: 48 pages, 4 tables. BlackHawk can be obtained at this https URL

Journal-ref: Eur.Phys.J. C79 (2019) no.8, 693

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

[71]  arXiv:1905.05440 (replaced) [pdf, other]

Title: Beam-deconvolved Planck LFI maps

Authors: E. Keihänen, V. Lindholm, M. Lopez-Caniego, M. Maris, M. Reinecke, A.-S. Suur-Uski

Comments: 12 pages, 7 figures

Journal-ref: A&A, 632, A1 (2019)

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

[72]  arXiv:1906.05726 (replaced) [pdf, other]

Title: Robust model comparison tests of DAMA/LIBRA annual modulation

Authors: Aditi Krishak, Aisha Dantuluri, Shantanu Desai

Comments: 13 pages, 2 figures. Additional sections on searches for higher harmonics and sensitivity of model comparison tests used here in distinguishing real signals from noise with synthetic data

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Instrumentation and Methods for Astrophysics (astro-ph.IM); High Energy Physics - Experiment (hep-ex)

[73]  arXiv:1907.02646 (replaced) [pdf, other]

Title: The origin of slow Alfvénic solar wind at solar minimum

Authors: D. Stansby, L. Matteini, T. S. Horbury, D. Perrone, R. D'Amicis, L. Berčič

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

[74]  arXiv:1907.02693 (replaced) [pdf, ps, other]

Title: Calibrating the standard candles with strong lensing

Authors: Xudong Wen, Kai Liao

Comments: 8 pages, 5 figures, 1 table, accepted by EPJC

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

[75]  arXiv:1907.06521 (replaced) [pdf]

Title: Virtual European Solar & Planetary Access (VESPA): a Planetary Science Virtual Observatory cornerstone

Authors: S. Erard, B. Cecconi, P. Le Sidaner, C. Chauvin, A. P. Rossi, M. Minin, T. Capria, S. Ivanovski, B. Schmitt, V. Genot, N. Andre, C. Marmo, A. C. Vandaele, L. Trompet, M. Scherf, R. Hueso, A. Maattanen, B. Carry, N. Achilleos, J. Soucek, D. Pisa, K. Benson, P. Fernique, E. Millour

Comments: Submitted to Data Science Journal

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

[76]  arXiv:1907.07599 (replaced) [pdf, other]

Title: Gamma-ray burst jet propagation, development of angular structure, and the luminosity function

Authors: O. S. Salafia, C. Barbieri, S. Ascenzi, M. Toffano

Comments: 15 pages, 12 figures. Revised version, submitted to A&A (several new figures and expanded discussion. Conclusions unchanged). Comments and suggestions are welcome!

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

[77]  arXiv:1907.09384 (replaced) [pdf, other]

Title: Search for Eccentric Binary Black Hole Mergers with Advanced LIGO and Advanced Virgo during their First and Second Observing Runs

Authors: The LIGO Scientific Collaboration, the Virgo Collaboration: B. P. Abbott, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, M. A. Aloy, P. A. Altin, A. Amato, S. Anand, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda, M. Arène, N. Arnaud, S. M. Aronson, K. G. Arun, S. Ascenzi, G. Ashton, S. M. Aston, P. Astone, F. Aubin, P. Aufmuth, K. AultONeal, C. Austin, V. Avendano, A. Avila-Alvarez, S. Babak, P. Bacon, F. Badaracco, M. K. M. Bader, S. Bae, J. Baird, P. T. Baker, F. Baldaccini, G. Ballardin, S. W. Ballmer, A. Bals, S. Banagiri, J. C. Barayoga, C. Barbieri, et al. (1124 additional authors not shown)

Comments: 7 pages, 2 figures

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

[78]  arXiv:1907.12843 (replaced) [pdf, other]

Title: Domain walls in neutron $^{3}P_{2}$ superfluids in neutron stars

Authors: Shigehiro Yasui, Muneto Nitta

Comments: 31 pages, 12 figures

Journal-ref: Phys.Rev. C 101, 015207 (2020)

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

[79]  arXiv:1907.13311 (replaced) [pdf, other]

Title: A universal threshold for primordial black hole formation

Authors: Albert Escrivà, Cristiano Germani, Ravi K. Sheth

Comments: 5 pages and 5 figures, v3: clarifications and more numerical evidences for the lower bound added. Version accepted in PRD

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

[80]  arXiv:1908.08032 (replaced) [pdf, other]

Title: Kinetic turbulence in shining pair plasma: intermittent beaming and thermalization by radiative cooling

Authors: Vladimir Zhdankin, Dmitri A. Uzdensky, Gregory R. Werner, Mitchell C. Begelman

Comments: 26 pages, 30 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society

Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Plasma Physics (physics.plasm-ph)

[81]  arXiv:1908.09277 (replaced) [pdf, ps, other]

Title: Inelastic extra $U(1)$ charged scalar dark matter

Authors: Nobuchika Okada, Osamu Seto

Comments: 26 pages, 12 figures, references and discussion added, the final journal published version

Journal-ref: Phys. Rev. D 101, 023522 (2020)

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

[82]  arXiv:1908.10590 (replaced) [pdf, other]

Title: Cosmological parameter estimation from large-scale structure deep learning

Authors: Shuyang Pan, Miaoxin Liu, Jaime Forero-Romero, Cristiano G. Sabiu, Zhigang Li, Haitao Miao, Xiao-Dong Li

Comments: 17 pages, 10 figures

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

[83]  arXiv:1908.10878 (replaced) [pdf, other]

Title: Axions as a probe of solar metals

Authors: Joerg Jaeckel, Lennert J. Thormaehlen

Comments: 6 pages, 3 figures, minor updates and corrections

Journal-ref: Phys. Rev. D 100, 123020 (2019)

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Physics - Phenomenology (hep-ph)

[84]  arXiv:1908.11609 (replaced) [pdf, other]

Title: A metric on the space of neutron star models in general relativity and modified gravity

Authors: Arthur G Suvorov

Comments: 6 pages, 1 figure. Accepted for publication in Classical and Quantum Gravity

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

[85]  arXiv:1909.00006 (replaced) [pdf, other]

Title: Elemental Abundances in M31: A Comparative Analysis of Iron and Alpha Element Abundances in the Outer Disk, Giant Stellar Stream, and Inner Halo of M31

Authors: Ivanna Escala, Karoline M. Gilbert, Evan N. Kirby, Jennifer Wojno, Emily C. Cunningham, Puragra Guhathakurta

Comments: 32 pages, 19 figures, 6 tables, ApJ in press

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

[86]  arXiv:1909.02978 (replaced) [pdf, other]

Title: Gravitational wave and collider signals in complex two-Higgs doublet model with dynamical CP-violation at finite temperature

Authors: Xiao Wang, Fa Peng Huang, Xinmin Zhang

Comments: Published version in Physical Review D, 35 pages, 9 figures, 7 tables

Journal-ref: Phys. Rev. D 101, 015015 (2020)

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

[87]  arXiv:1909.05240 (replaced) [pdf, ps, other]

Title: The formation of young massive clusters triggered by cloud-cloud collisions in the Antennae Galaxies NGC 4038/NGC 4039

Authors: Kisetsu Tsuge, Yasuo Fukui, Kengo Tachihara, Hidetoshi Sano, Kazuki Tokuda, Junko Ueda, Daisuke Iono, Molly K. Finn

Comments: 32 pages, 22 figures, 4 tables , accepted for the Publications of the Astronomical Society of Japan (PASJ)

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

[88]  arXiv:1909.05804 (replaced) [pdf, other]

Title: Black holes in the low mass gap: Implications for gravitational wave observations

Authors: Anuradha Gupta, Davide Gerosa, K. G. Arun, Emanuele Berti, B. S. Sathyaprakash

Comments: 7 pages, 4 figures, 1 table. v2: added a discussion on primary of GW190425 being a second generation BH in the low mass-gap

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

[89]  arXiv:1909.09158 (replaced) [pdf, other]

Title: Searching for a cometary belt around Trappist-1 with ALMA

Authors: S. Marino, M. C. Wyatt, G. M. Kennedy, M. Kama, L. Matrà, A. H. M. J. Triaud, Th. Henning

Comments: accepted for publication in MNRAS, 7 pages, 5 figures

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

[90]  arXiv:1909.09162 (replaced) [pdf, other]

Title: On the origin of the chemical bimodality of disk stars: A tale of merger and migration

Authors: Tobias Buck (AIP)

Comments: 13 pages, 9 main text, 7 figures plus 3 in appendix, accepted by MNRAS

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

[91]  arXiv:1909.10002 (replaced) [pdf, other]

Title: Detection of gamma-ray transients with wild binary segmentation

Authors: Sarah Antier, Kateryna Barynova, Piotr Fryzlewicz, Cyril Lachaud, Gerard Marchal-Duval

Comments: 15 pages, 5 figures

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

[92]  arXiv:1910.02297 (replaced) [pdf, other]

Title: Comparing Observed Stellar Kinematics and Surface Densities in a Low Latitude Bulge Field to Galactic Population Synthesis Models

Authors: Sean K. Terry, Richard K. Barry, David P. Bennett, Aparna Bhattacharya, Jay Anderson, Matthew T. Penny

Comments: 18 pages, 10 figures. Published in ApJ

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

[93]  arXiv:1910.04587 (replaced) [pdf, other]

Title: The Probability Distribution of Astrophysical Gravitational-Wave Background Fluctuations

Authors: Yonadav Barry Ginat, Vincent Desjacques, Robert Reischke, Hagai B. Perets

Comments: Submitted for publication. Comments welcome

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

[94]  arXiv:1910.06074 (replaced) [pdf, ps, other]

Title: Magnetic helicity dissipation and production in an ideal MHD code

Authors: Axel Brandenburg, Evan Scannapieco

Comments: 9 pages, 14 figures, 2 tables, ApJ 889, 55 (2020)

Journal-ref: Astrophys. J. 889, 55 (2020)

Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA); Fluid Dynamics (physics.flu-dyn)

[95]  arXiv:1910.07605 (replaced) [pdf, other]

Title: Near-Infrared Imaging of a Spiral in the CQ Tau Disk

Authors: Taichi Uyama, Takayuki Muto, Dimitri Mawet, Valentin Christiaens, Jun Hashimoto, Tomoyuki Kudo, Masayuki Kuzuhara, Garreth Ruane, Charles Beichman, Olivier Absil, Eiji Akiyama, Jaehan Bae, Michael Bottom, Elodie Choquet, Thayne Currie, Ruobing Dong, Katherine B. Follette, Misato Fukagawa, Greta Guidi, Elsa Huby, Jungmi Kwon, Satoshi Mayama, Tiffany Meshkat, Maddalena Reggiani, Luca Ricci, Eugene Serabyn, Motohide Tamura, Leonardo Testi, Nicole Wallack, Jonathan Williams, Zhaohuan Zhu

Comments: accepted for publication in AJ

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

[96]  arXiv:1910.07981 (replaced) [pdf, other]

Title: Mass bound for primordial black hole from trans-Planckian censorship conjecture

Authors: Rong-Gen Cai, Shao-Jiang Wang

Comments: v1, 6 pages, 2 figures; v2, references added; v3, presentation improved, accepted by PRD

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

[97]  arXiv:1910.09377 (replaced) [pdf, other]

Title: Direct Imaging of Irregular Satellite Disks in Scattered Light

Authors: Loic Nassif-Lachapelle, Daniel Tamayo

Comments: 11 pages, accepted in MNRAS

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

[98]  arXiv:1910.10216 (replaced) [pdf, other]

Title: Solitons in the Einstein universe

Authors: Eugene B. Kolomeisky, Ephraiem Sarabamoun

Comments: 7 pages, 3 figures, slight change of the title, minor changes of the text, version to be published in Phys. Rev. D

Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Pattern Formation and Solitons (nlin.PS); Plasma Physics (physics.plasm-ph)

[99]  arXiv:1911.01430 (replaced) [pdf, other]

Title: The Sloan Digital Sky Survey extended point spread functions

Authors: Raúl Infante-Sainz, Ignacio Trujillo, Javier Román

Comments: Minor corrections of editor included. Available PSFs at this http URL This paper is fully reproducible, see instructions at this https URL, and in Zenodo at this https URL

Journal-ref: MNRAS, 491, 2020, 5317

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

[100]  arXiv:1911.03191 (replaced) [pdf, other]

Title: MeV-GeV $γ$-ray telescopes probing axino LSP/gravitino NLSP as dark matter in the $μν$SSM

Authors: German A. Gomez-Vargas, Daniel E. Lopez-Fogliani, Carlos Munoz, Andres D. Perez

Comments: Version published in JCAP, discussions expanded, references added, 27 pages, 6 figures

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

[101]  arXiv:1911.09110 (replaced) [src]

Title: Neutrino propagation hinders fast pairwise flavor conversions

Authors: Shashank Shalgar, Ian Padilla-Gay, Irene Tamborra

Comments: An error was found in the numerical runs. A new version will be submitted as soon as possible

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

[102]  arXiv:1912.04662 (replaced) [pdf, other]

Title: A companion star launching jets in the wind acceleration zone of a giant star

Authors: Shlomi Hillel, Ron Schreier, Noam Soker (Technion, Israel)

Comments: Accepted for publication in The Astrophysical Journal

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

[103]  arXiv:1912.05556 (replaced) [pdf, ps, other]

Title: GJ 1252 b: A 1.2 $R_{\oplus}$ planet transiting an M3-dwarf at 20.4 pc

Authors: Avi Shporer, Karen A. Collins, Nicola Astudillo-Defru, Jonathan Irwin, Xavier Bonfils, Kevin I. Collins, Elisabeth Matthews, Jennifer G. Winters, David R. Anderson, James D. Armstrong, David Charbonneau, Ryan Cloutier, Tansu Daylan, Tianjun Gan, Maximilian N. Günther, Coel Hellier, Keith Horne, Chelsea X. Huang, Eric L. N. Jensen, John Kielkopf, Enric Palle, Ramotholo Sefako, Keivan G. Stassun, Thiam-Guan Tan, Andrew Vanderburg, George R. Ricker, David W. Latham, Roland Vanderspek, Sara Seager, Joshua N. Winn, Jon M. Jenkins, Knicole Colon, Courtney D. Dressing, Sébastien Lépine, Philip S. Muirhead, Mark E. Rose, Joseph D. Twicken, Jesus Noel Villasenor

Comments: Accepted to ApJ Letters

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

[104]  arXiv:1912.06478 (replaced) [pdf, ps, other]

Title: The quantum black hole as a gravitational hydrogen atom

Authors: Christian Corda, Fabiano Feleppa

Comments: 20 pages

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

[105]  arXiv:2001.00289 (replaced) [pdf, ps, other]

Title: Repeated state change of variable gamma-ray pulsar, PSR J2021+4026

Authors: J. Takata, H.H. Wang, L.C.C. Lin, C.-P. Hu, C.Y. Hui, A.K.H. Kong, P.H.T. Tam, K.L. Li, K.S. Cheng

Comments: 20 pages, 6 figures. Accepted for publication in ApJ

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

[106]  arXiv:2001.00563 (replaced) [pdf, other]

Title: Using Data Imputation for Signal Separation in High Contrast Imaging

Authors: Bin Ren, Laurent Pueyo, Christine Chen, Élodie Choquet, John H. Debes, Gaspard Duchêne, François Ménard, Marshall D. Perrin

Comments: 18 pages, 9 figures, ApJ accepted. Modified AASTeX template at this https URL

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

[107]  arXiv:2001.00673 (replaced) [pdf]

Title: There's No Place Like Home (in Our Own Solar System): Searching for ET Near White Dwarfs

Authors: John Gertz

Comments: Published in JBIS Vol. 72 No. 11 November 2019

Journal-ref: JBIS Vol. 72 No. 11 November 2019

Subjects: Popular Physics (physics.pop-ph); Earth and Planetary Astrophysics (astro-ph.EP)

[108]  arXiv:2001.01530 (replaced) [pdf, other]

Title: Galactic Magnetic Field Bias on Inferences from UHECR Data

Authors: Björn Eichmann, Tobias Winchen

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

[109]  arXiv:2001.01643 (replaced) [pdf, other]

Title: Monitoring of the radio galaxy M87 during a low emission state from 2012 to 2015 with MAGIC

Authors: MAGIC Collaboration: V. A. Acciari (1), S. Ansoldi (2,23), L. A. Antonelli (3), A. Arbet Engels (4), C. Arcaro (29,30), D. Baack (5), A. Babić (6), B. Banerjee (7), P. Bangale (14), 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), 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), et al. (147 additional authors not shown)

Comments: 12 pages, 4 figures, accepted on MNRAS

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

[110]  arXiv:2001.03177 (replaced) [pdf, other]

Title: The Chemical Compositions of Accreted and {\it in situ} Galactic Globular Clusters According to SDSS/APOGEE

Authors: Danny Horta, Ricardo P. Schiavon, J. Ted Mackereth, Timothy C. Beers, José G. Fernández-Trincado, Peter M. Frinchaboy, D.A. García-Hernández, Doug Geisler, Sten Hasselquist, Henrik Jönsson, Richard R. Lane, Steven R. Majewski, Szabolcs Mészáros, Christian Moni Bidin, David M. Nataf, Alexandre Roman-Lopes, Christian Nitschelm, Jaime Vargas-González, Gail Zasowski

Comments: 18 pages, 10 figures, 3 tables. Re-submitted to MNRAS following moderate revisions

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

[111]  arXiv:2001.06683 (replaced) [pdf]

Title: The Habitable Exoplanet Observatory (HabEx) Mission Concept Study Final Report

Authors: B. Scott Gaudi, Sara Seager, Bertrand Mennesson, Alina Kiessling, Keith Warfield, Kerri Cahoy, John T. Clarke, Shawn Domagal-Goldman, Lee Feinberg, Olivier Guyon, Jeremy Kasdin, Dimitri Mawet, Peter Plavchan, Tyler Robinson, Leslie Rogers, Paul Scowen, Rachel Somerville, Karl Stapelfeldt, Christopher Stark, Daniel Stern, Margaret Turnbull, Rashied Amini, Gary Kuan, Stefan Martin, Rhonda Morgan, David Redding, H. Philip Stahl, Ryan Webb, Oscar Alvarez-Salazar, William L. Arnold, Manan Arya, Bala Balasubramanian, Mike Baysinger, Ray Bell, Chris Below, Jonathan Benson, Lindsey Blais, Jeff Booth, Robert Bourgeois, Case Bradford, Alden Brewer, Thomas Brooks, Eric Cady, Mary Caldwell, Rob Calvet, Steven Carr, Derek Chan, Velibor Cormarkovic, Keith Coste, Charlie Cox, Rolf Danner, Jacqueline Davis, et al. (134 additional authors not shown)

Comments: Full report: 498 pages. Executive Summary: 14 pages. More information about HabEx can be found here: this https URL

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

[112]  arXiv:2001.08225 (replaced) [pdf, ps, other]

Title: A multiplicity study of transiting exoplanet host stars. II. Revised properties of transiting planetary systems with companions

Authors: J. Southworth, A. J. Bohn, M. A. Kenworthy, C. Ginski, L. Mancini

Comments: Accepted for publication in A&A (12 pages, 7 figures, 7 tables). Version 2 includes language corrections and a revised orbital ephemeris for WASP-76

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

[113]  arXiv:2001.08547 (replaced) [pdf, other]

Title: Thermal and radiation driving can produce observable disk winds in hard-state X-ray binaries

Authors: Nick Higginbottom, Christian Knigge, Stuart A. Sim, Knox S. Long, James H. Matthews, Henrietta A. Hewitt, Edward J. Parkinson, Sam W. Mangham

Comments: Accepted for publication by MNRAS

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

[114]  arXiv:2001.08752 (replaced) [pdf, other]

Title: The Ultraluminous X-ray sources population of the galaxy NGC 7456

Authors: F. Pintore, M. Marelli, R. Salvaterra, G. L. Israel, G. A. Rodríguez Castillo, P. Esposito, A. Belfiore, A. De Luca, A. Wolter, S. Mereghetti, L. Stella, M. Rigoselli, H. P. Earnshaw, C. Pinto, T. P. Roberts, D. J. Walton, F. Bernardini, F. Haberl, C. Salvaggio, A. Tiengo, L. Zampieri, M. Bachetti, M. Brightman, P. Casella, D. D'Agostino, S. Dall'Osso, F. Fuerst, F. A. Harrison, M. Mapelli, A. Papitto, M. Middleton

Comments: Accepted on ApJ; 10 pages, 5 figures, 3 tables

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

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