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New submissions for Tue, 3 Mar 20

[1]  arXiv:2003.00013 [pdf, other]

Title: The ALPINE-ALMA [CII] Survey: Size of Individual Star-Forming Galaxies at z=4-6 and their Extended Halo Structure

Authors: S. Fujimoto, J. D. Silverman, Matthieu Bethermin, M. Ginolfi, G. C. Jones, O. Le Fèvre, M. Dessauges-Zavadsky, W. Rujopakarn, A. L. Faisst, Y. Fudamoto, P. Cassata, L. Morselli, D. Schaerer, P. Capak, L. Yan, L. Vallini, S. Toft, F. Loiacono, G. Zamorani, M. Talia, D. Narayanan, N. P. Hathi, B. C. Lemaux, Médéric Boquien, R. Amorin, E. Ibar, A. M. Koekemoer H. Méndez-Hernández, Sandro Bardelli, D. Vergani, E. Zucca, M. Romano, A. Cimatti

Comments: 20 pages, 10 figures, submitted to ApJ

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

We present the physical extent of [CII] 158um line-emitting gas from 46 star-forming galaxies at z=4-6 from the ALMA Large Program to INvestigate CII at Early Times (ALPINE). Using exponential profile fits, we measure the effective radius of the [CII] line (r_e,[CII]) for individual galaxies and compare them with the rest-frame ultra-violet (UV) continuum (r_e,UV) from Hubble Space Telescope images. The effective radius r_e,[CII] almost always exceeds r_e,UV by factors of ~2-3 and the ratio of r_e,[CII]/r_e,UV increases as a function of M_star. We do not find strong evidence for a displacement over ~ 1-kpc scale among the [CII] line, the rest-frame UV, and FIR continuum. We identify 30% of isolated ALPINE sources as having an extended [CII] component over 10-kpc scales detected at 4.1$\sigma$-10.9$\sigma$ beyond the size of rest-frame UV and far-infrared (FIR) continuum. One object has tentative rotating features up to ~10-kpc, where the 3D model fit shows the rotating [CII]-gas disk spread over 4 times larger than the rest-frame UV-emitting region. Galaxies with the extended [CII] line structure have high star-formation rate (SFR), stellar mass (M_star), low Lya equivalent-width, and more blue-shifted (red-shifted) rest-frame UV metal absorption (Lya line), as compared to galaxies without such extended [CII] structures. Although we cannot rule out the possibility that a selection bias towards luminous objects may be responsible for such trends, the extended [CII] line structure appears even around several objects whose SFR and M_star are as small as those without the extended structure. Deeper observations are essential to test whether the extended [CII] line structures are ubiquitous to high-z star-forming galaxies.

[2]  arXiv:2003.00015 [pdf, other]

Title: Double X/Peanut Structures in Barred Galaxies -- Insights from an $N$--body Simulation

Authors: Bogdan C. Ciambur, Francesca Fragkoudi, Sergey Khoperskov, Paola Di Matteo, Françoise Combes

Comments: 12 pages, 11 figures

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

Boxy, peanut- or X-shaped "bulges" are observed in a large fraction of barred galaxies viewed in, or close to, edge-on projection, as well as in the Milky Way. They are the product of dynamical instabilities occurring in stellar bars, which cause the latter to buckle and thicken vertically. Recent studies have found nearby galaxies that harbour two such features arising at different radial scales, in a nested configuration. In this paper we explore the formation of such double peanuts, using a collisionless N-body simulation of a pure disc evolving in isolation within a live dark matter halo, which we analyse in a completely analogous way to observations of real galaxies. In the simulation we find a stable double configuration consisting of two X/peanut structures associated to the same galactic bar - rotating with the same pattern speed - but with different morphology, formation time, and evolution. The inner, conventional peanut-shaped structure forms early via the buckling of the bar, and experiences little evolution once it stabilises. This feature is consistent in terms of size, strength and morphology, with peanut structures observed in nearby galaxies. The outer structure, however, displays a strong X, or "bow-tie", morphology. It forms just after the inner peanut, and gradually extends in time (within 1 to 1.5 Gyr) to almost the end of the bar, a radial scale where ansae occur. We conclude that, although both structures form, and are dynamically coupled to, the same bar, they are supported by inherently different mechanisms.

[3]  arXiv:2003.00016 [pdf, other]

Title: Three Dusty Star Forming Galaxies at $z\sim1.5$: Mergers and Disks on the Main Sequence

Authors: Patrick M. Drew, Caitlin M. Casey, Asantha Cooray, Katherine E. Whitaker

Comments: 8 pages, 5 figures, accepted for publication in ApJ

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

The main sequence of galaxies, a correlation between the star formation rates and stellar masses of galaxies, has been observed out to $z\sim4$. Galaxies within the scatter of the correlation are typically interpreted to be secularly evolving while galaxies with star formation rates elevated above the main sequence are interpreted to be undergoing interactions or to be Toomre-unstable disks with starbursting clumps. In this paper we investigate the recent merger histories of three dusty star forming galaxies, identified by their bright submillimeter emission at $z\sim1.5$. We analyze rest-frame optical and UV imaging, rest-frame optical emission line kinematics using slit spectra obtained with MOSFIRE on Keck I, and calculate Gini and M$_{20}$ statistics for each galaxy and conclude two are merger-driven while the third is an isolated disk galaxy. The disk galaxy lies $\sim$4$\times$ above the main sequence, one merger lies within the scatter of the main sequence, and one merger lies $\sim$4$\times$ below the main sequence. This hints that the location of a galaxy with respect to the main sequence may not be a useful discriminator of the recent star formation history of high-M$_{\star}$ galaxies at $z\sim1$.

[4]  arXiv:2003.00017 [pdf, other]

Title: From parallel to perpendicular -- On the orientation of magnetic fields in molecular clouds

Authors: D. Seifried, S. Walch, M. Weis, S. Reissl, J. D. Soler, R. S. Klessen, P. R. Joshi

Comments: 17 pages, 11 figures, submitted to MNRAS, comments are welcome

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

We present synthetic dust polarization maps of simulated molecular clouds (MCs) with the goal to systematically explore the origin of the relative orientation of the magnetic field ($\bf{B}$) with respect to the MC sub-structures identified in density ($n$; 3D) and column density ($N$; 2D). The polarization maps are generated with the radiative transfer code POLARIS, including self-consistently calculated efficiencies for radiative torque alignment. The MCs are formed in two sets of 3D MHD simulations: in (i) colliding flows (CF), and (ii) the SILCC-Zoom simulations. In 3D, for the CF simulations with an initial field strength below $\sim$5 $\mu$G, $\bf{B}$ is oriented parallel or randomly with respect to the $n$-structures. For CF runs with stronger initial fields and all SILCC-Zoom simulations, which have an initial field strength of 3 $\mu$G, a flip from parallel to perpendicular orientation occurs at high densities of $n_\text{trans}$ $\simeq$ 10$^2$ - 10$^3$ cm$^{-3}$. We suggest that this flip happens if the MC's mass-to-flux ratio, $\mu$, is close to or below the critical value of 1. This corresponds to a field strength around 3 - 5 $\mu$G. In 2D, we use the Projected Rayleigh Statistics (PRS) to study the orientation of $\bf{B}$. If present, the flip in orientation occurs at $N_\text{trans}$ $\simeq$ 10$^{21 - 21.5}$ cm$^{-2}$, similar to the observed transition value from sub- to supercritical magnetic fields in the ISM. However, projection effects can reduce the power of the PRS method: Depending on the MC or LOS, the projected maps of the SILCC-Zoom simulations do not always show the flip, although expected from the 3D morphology. Such projection effects can explain the variety of recently observed field configurations, in particular within a single MC. Finally, we do not find a correlation between the observed orientation of $\bf{B}$ and the $N$-PDF.

[5]  arXiv:2003.00019 [pdf, other]

Title: Venturing beyond the ISCO: Detecting X-ray emission from the plunging regions around black holes

Authors: D.R. Wilkins, C.S. Reynolds, A.C. Fabian

Comments: 20 pages, 12 figures. Accepted for publication in MNRAS

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

We explore how X-ray reverberation around black holes may reveal the presence of the innermost stable circular orbit (ISCO), predicted by General Relativity, and probe the dynamics of the plunging region between the ISCO and the event horizon. Being able to directly detect the presence of the ISCO and probe the dynamics of material plunging through the event horizon represents a unique test of general relativity in the strong field regime. X-ray reverberation off of the accretion disc and material in the plunging region is modelled using general relativistic ray tracing simulations. X-ray reverberation from the plunging region has a minimal effect on the time-averaged X-ray spectrum and the overall lag-energy spectrum, but is manifested in the lag in the highest frequency Fourier components, above 0.01 c^3 (GM)^-1 (scaled for the mass of the black hole) in the 2-4keV energy band for a non-spinning black hole or the 1-2keV energy band for a maximally spinning black hole. The plunging region is distinguished from disc emission not just by the energy shifts characteristic of plunging orbits, but by the rapid increase in ionisation of material through the plunging region. Detection requires measurement of time lags to an accuracy of 20 per cent at these frequencies. Improving accuracy to 12 per cent will enable constraints to be placed on the dynamics of material in the plunging region and distinguish plunging orbits from material remaining on stable circular orbits, confirming the existence of the ISCO, a prime discovery space for future X-ray missions.

[6]  arXiv:2003.00020 [pdf, ps, other]

Title: The white dwarf planet WD J0914+1914 b: barricading potential rocky pollutants?

Authors: Dimitri Veras

Comments: Accepted for publication in MNRAS

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

An ice giant planet was recently reported orbiting white dwarf WD J0914+1914 at an approximate distance of 0.07 au. The striking non-detection of rocky pollutants in this white dwarf's photosphere contrasts with the observations of nearly every other known white dwarf planetary system. Here, I analyze the prospects for exterior extant rocky asteroids, boulders, cobbles and pebbles to radiatively drift inward past the planet due to the relatively high luminosity (0.1 L_Sun) of this particularly young (13 Myr) white dwarf. Pebbles and cobbles drift too slowly from Poynting-Robertson drag to bypass the planet, but boulders and asteroids are subject to the much stronger Yarkovsky effect. In this paper, I (i) place lower limits on the timescales for these objects to reach the planet's orbit, (ii) establish 3 m as the approximate limiting radius above which a boulder drifts too slowly to avoid colliding with the planet, and (iii) compute bounds on the fraction of boulders which succeed in traversing mean motion resonances and the planet's Hill sphere to eventually pollute the star. Overall, I find that the planet acts as a barrier against rather than a facilitator for radiatively-driven rocky pollution, suggesting that future rocky pollutants would most likely originate from distant scattering events.

[7]  arXiv:2003.00028 [pdf, other]

Title: An ultra-massive white dwarf with a mixed hydrogen-carbon atmosphere as a likely merger remnant

Authors: Mark A. Hollands, Pier-Emmanuel Tremblay, Boris T. Gänsicke, María E. Camisassa, Detlev Koester, Amornrat Aungwerojwit, Paul Chote, Alejandro H. Córsico, Vik S. Dhillon, Nicola P. Gentile-Fusillo, Matthew J. Hoskin, Paula Izquierdo, Tom R. Marsh, Danny Steeghs

Comments: Published in Nature Astronomy Letters on March 2nd 2020, this https URL

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

White dwarfs are dense, cooling stellar embers consisting mostly of carbon and oxygen, or oxygen and neon (with a few percent carbon) at higher initial stellar masses. These stellar cores are enveloped by a shell of helium which in turn is usually surrounded by a layer of hydrogen, generally prohibiting direct observation of the interior composition. However, carbon is observed at the surface of a sizeable fraction of white dwarfs, sometimes with traces of oxygen, and it is thought to be dredged-up from the core by a deep helium convection zone. In these objects only traces of hydrogen are found as large masses of hydrogen are predicted to inhibit hydrogen/helium convective mixing within the envelope. We report the identification of WDJ055134.612+413531.09, an ultra-massive (1.14 $M_\odot$) white dwarf with a unique hydrogen/carbon mixed atmosphere (C/H=0.15 in number ratio). Our analysis of the envelope and interior indicates that the total hydrogen and helium mass fractions must be several orders of magnitude lower than predictions of single star evolution: less than $10^{-9.5}$ and $10^{-7.0}$, respectively. Due to the fast kinematics ($129\pm5$ km/s relative to the local standard of rest), large mass, and peculiar envelope composition, we argue that WDJ0551+4135 is consistent with formation from the merger of two white dwarfs in a tight binary system.

[8]  arXiv:2003.00065 [pdf, other]

Title: Gravitational waves from Population III binary black holes formed by dynamical capture

Authors: Boyuan Liu, Volker Bromm

Comments: 22 pages, 15+6 figures, submitted to MNRAS

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

We use cosmological hydrodynamic simulations to study the gravitational wave (GW) signals from high-redshift binary black holes (BBHs) formed by dynamical capture (ex-situ formation channel). We in particular focus on BHs originating from the first generation of massive, metal-poor, so-called Population III (Pop III) stars. An alternative (in-situ) formation pathway arises in Pop III binary stars, whose GW signature has been intensively studied. We predict a local GW event rate density for ex-situ BBHs (formed at $z> 4$) of $\sim 0.001-0.1\ \mathrm{yr^{-1}\ Gpc^{-3}}$. This is comparable to or even higher than the rate density predicted for in-situ BBHs, indicating that the ex-situ formation channel may be as important as the in-situ one for producing GW events. We also evaluate the detectability of BH-BH merger events from our simulated BBHs for select planned GW instruments, such as the Einstein Telescope (ET) and Decihertz observatories (DOs). For instance, we find the all-sky detection rates with signal-to-noise ratios above 10 to be $\sim 10-200\ \rm{yr^{-1}}$ for the xylophone configuration of ET and the optimal DO, with uncertainties arising from our sub-grid model for the evolution of ex-situ BBHs.

[9]  arXiv:2003.00076 [pdf, other]

Title: Predicting accreted satellite galaxy masses and accretion redshifts based on globular cluster orbits in the E-MOSAICS simulations

Authors: Joel L. Pfeffer, Sebastian Trujillo-Gomez, J. M. Diederik Kruijssen, Robert A. Crain, Meghan E. Hughes, Marta Reina-Campos, Nate Bastian

Comments: 12 pages, 6 figures. Submitted to MNRAS

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

The ages and metallicities of globular clusters (GCs) are known to be powerful tracers of the properties of their progenitor galaxies, enabling their use in determining the merger histories of galaxies. However, while useful in separating GCs into individual accretion events, the orbits of GC groups themselves have received less attention as probes of their progenitor galaxy properties. In this work, we use simulations of galaxies and their GC systems from the E-MOSAICS project to explore how the present-day orbital properties of GCs are related to the properties of their progenitor galaxies. We find that the orbits of GCs deposited by accretion events are sensitive to the mass and merger redshift of the satellite galaxy. Earlier mergers and larger galaxy masses deposit GCs at smaller median apocentres and lower total orbital energy. The orbital properties of accreted groups of GCs can therefore be used to infer the properties of their progenitor galaxy, though there exists a degeneracy between galaxy mass and accretion time. Combining GC orbits with other tracers (GC ages, metallicities) will help to break the galaxy mass/accretion time degeneracy, enabling stronger constraints on the properties of their progenitor galaxy. In situ GCs generally orbit at lower energies (small apocentres) than accreted GCs, however they exhibit a large tail to high energies and even retrograde orbits (relative to the present-day disc), showing significant overlap with accreted GCs. Applying the results to Milky Way GCs groups suggests a merger redshift $z \sim 1.5$ for the Gaia Sausage/Enceladus and $z>2$ for the `low-energy'/Kraken group, adding further evidence that the Milky Way had two significant mergers in its past.

[10]  arXiv:2003.00079 [pdf, other]

Title: Dust depleted inner disks in a large sample of transition disks through long-baseline ALMA observations

Authors: Logan Francis, Nienke van der Marel

Comments: 31 pages, 14 figures, accepted for publication in the Astrophysical Journal

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

Transition disks with large inner dust cavities are thought to host massive companions. However, the disk structure inside the companion orbit and how material flows toward an actively accreting star remain unclear. We present a high resolution continuum study of inner disks in the cavities of 38 transition disks. Measurements of the dust mass from archival Atacama Large Millimeter/Submillimeter Array observations are combined with stellar properties and spectral energy distributions to assemble a detailed picture of the inner disk. An inner dust disk is detected in 18 of 38 disks in our sample. Of the 14 resolved disks, 9 are significantly misaligned with the outer disk. The near-infrared excess is uncorrelated with the mm dust mass of the inner disk. The size-luminosity correlation known for protoplanetary disks is recovered for the inner disks as well, consistent with radial drift. The inner disks are depleted in dust relative to the outer disk and their dust mass is uncorrelated with the accretion rates. This is interpreted as the result of radial drift and trapping by planets in a low $\alpha$ ($\sim 10^{-3}$) disk, or a failure of the $\alpha$-disk model to describe angular momentum transport and accretion. The only disk in our sample with confirmed planets in the gap, PDS 70, has an inner disk with a significantly larger radius and lower inferred gas-to-dust ratio than other disks in the sample. We hypothesize that these inner disk properties and the detection of planets are due to the gap having only been opened recently by young, actively accreting planets.

[11]  arXiv:2003.00087 [pdf, other]

Title: CCD \emph{VI} time-series of the extremely metal poor globular cluster M92: revisiting its variable star population

Authors: M. A. Yepez, A. Arellano Ferro, D. Deras

Comments: 15 pages, 17 figures, 6 tables, accepted for publication in MNRAS 2020 February 27

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

We present an analysis of \emph{VI} CCD time-series photometry of the Oo II type globular cluster M92. The variable star population of the cluster is studied with the aim of revising their classifications, identifications, frequency spectra and to select indicators of the parental cluster metallicity and distance. The Fourier decomposition of RR Lyrae light curves lead to the estimation of mean [Fe/H]$_{\rm spec}=-2.20\pm 0.18$, and distance of $8.3\pm0.2$ kpc. Four new variables are reported; one RRd (V40), a multimode SX Phe (V41), a SR (V42) and one RRc (F1) that is most likely not a cluster member. The AC nature of V7 is confirmed. The double mode nature of the RRc star V11 is not confirmed and its amplitude modulations are most likely due to the Blazhko effect. Two modes are found in the known RRc variable V13. It is argued that the variable V30, previously classified as RRab is, in fact, an BL Her-type star not belonging to the cluster. Making use of the $Gaia$-DR2 proper motions, we identified 5012 stars in the field of the cluster, that are very likely cluster members, and for which we possess photometry, enabling the production of a refined Colour-Magnitude Diagram. This also allowed us to identify a few variable stars that do not belong to the cluster. The RR Lyrae pulsation modes on the HB are cleanly separated by the first overtone red edge, a common feature in all Oo II type clusters.

[12]  arXiv:2003.00109 [pdf, other]

Title: Density Based Outlier Scoring on Kepler Data

Authors: Daniel Giles, Lucianne Walkowicz

Comments: 14 pages, 10 figures, plus appendices, 4 supplemental tables hosted online

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

In the present era of large scale surveys, big data presents new challenges to the discovery process for anomalous data. Such data can be indicative of systematic errors, extreme (or rare) forms of known phenomena, or most interestingly, truly novel phenomena which exhibit as-of-yet unobserved behaviors. In this work we present an outlier scoring methodology to identify and characterize the most promising unusual sources to facilitate discoveries of such anomalous data. We have developed a data mining method based on k-Nearest Neighbor distance in feature space to efficiently identify the most anomalous lightcurves. We test variations of this method including using principal components of the feature space, removing select features, the effect of the choice of k, and scoring to subset samples. We evaluate the peformance of our scoring on known object classes and find that our scoring consistently scores rare (<1000) object classes higher than common classes. We have applied scoring to all long cadence lightcurves of quarters 1 to 17 of Kepler's prime mission and present outlier scores for all 2.8 million lightcurves for the roughly 200k objects.

[13]  arXiv:2003.00135 [pdf, other]

Title: The MAVERIC survey: A hidden pulsar and a black hole candidate in ATCA radio imaging of the globular cluster NGC 6397

Authors: Yue Zhao (1), Craig O. Heinke (1), Vlad Tudor (2), Arash Bahramian (2), James C. A. Miller-Jones (2), Gregory R. Sivakoff (1), Jay Strader (3), Laura Chomiuk (3), Laura Shishkovsky (3), Thomas J. Maccarone (4), Manuel Pichardo Marcano (4), Joseph D. Gelfand (5,6) ((1) University of Alberta, (2) International Centre for Radio Astronomy Research-Curtin University, (3) Michigan State University, (4) Texas Tech University, (5) New York University Abu Dhabi, (6) NYU Center for Cosmology and Particle Physics)

Comments: Accepted for publication in Monthly Notices of the Royal Astronomical Society. 18 pages, 9 figures, 4 tables

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

Using a 16.2 hr radio observation by the Australia Telescope Compact Array (ATCA) and archival Chandra data, we found $>5\sigma$ radio counterparts to 4 known and 3 new X-ray sources within the half-light radius ($r_\mathrm{h}$) of the Galactic globular cluster NGC 6397. The previously suggested millisecond pulsar (MSP) candidate, U18, is a steep-spectrum ($S_\nu \propto \nu^\alpha$; $\alpha=-2.0^{+0.4}_{-0.5}$) radio source with a 5.5 GHz flux density of $54.7\pm 4.3~\mathrm{\mu Jy}$. We argue that U18 is most likely a "hidden" MSP that is continuously hidden by plasma shocked at the collision between the winds from the pulsar and companion star. The nondetection of radio pulsations so far is probably the result of enhanced scattering in this shocked wind. On the other hand, we observed 5.5 GHz flux of the known MSP PSR J1740-5340 (U12) to decrease by a factor of $>2.8$ during epochs of 1.4 GHz eclipse, indicating that the radio flux is absorbed in its shocked wind. If U18 is indeed a pulsar whose pulsations are scattered, we note the contrast with U12's flux decrease in eclipse, which argues for two different eclipse mechanisms at the same radio frequency. In addition to U12 and U18, we also found radio associations for 5 other Chandra X-ray sources, four of which are likely background galaxies. The last, U97, which shows strong H$\alpha$ variability, is mysterious; it may be either a quiescent black hole low-mass X-ray binary, or something more unusual.

[14]  arXiv:2003.00148 [pdf, other]

Title: Entering the Era of Dark Matter Astronomy? Near to Long-Term Forecasts in X-Ray and Gamma-Ray Bands

Authors: Dawei Zhong, Mauro Valli, Kevork N. Abazajian

Comments: 18 pages, 12 figures, 1 table. Comments are welcome

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

We assess Galactic Dark Matter (DM) sensitivities to photons from annihilation and decay using the spatial and kinematic information determined by state-of-the-art simulations in the Latte suite of Feedback In Realistic Environments (FIRE-2). For kinematic information, we study the energy shift pattern of DM narrow emission lines predicted in FIRE-2 and discuss its potential as DM-signal diagnosis, showing for the first time the power of symmetric observations around $l=0^{\circ}$. We find that the exposures needed to resolve the line separation of DM to gas by XRISM at $5\sigma$ to be large, $\gtrsim 4$ Ms, while exposures are smaller for Athena ($\lesssim 500$ ks) and Lynx ($\lesssim 100$ ks). We find that large field of view (FOV) exposures remain the most sensitive methods for detection of dark matter annihilation or decay by the luminosity of signals in the field of view dominating velocity information. The $\sim$4 sr view of the Galactic Center region by the Wide Field Monitor aboard the enhanced X-ray Timing and Polarimetry (eXTP) mission will be highly sensitive to DM signals, with a prospect of $\approx\! 2\times 10^6$ events from the 3.5 keV line in a 10 ks exposure. We also investigate detailed all-sky luminosity maps for both DM annihilation and decay signals, evaluating the signal-to-noise for a DM detection, taking into account realistic X-ray and gamma-ray backgrounds, as a guideline for what could be a forthcoming era of DM astronomy.

[15]  arXiv:2003.00159 [pdf, other]

Title: When does the onset of multiple stellar populations in star clusters occur-III: No evidence of significant chemical variations in main-sequence stars of NGC 419

Authors: Chengyuan Li, Yue Wang, Baitian Tang, Antonino P. Milone, Yujiao Yang, Xin Ji

Comments: 11 pages, 5 figure, ApJ accepted

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

Recent studies have revealed that the onset age for the presence of multiple stellar populations (MPs) in star clusters seems to correspond to the disappearance of the extended main-sequence turnoff (eMSTO) in young clusters, a pattern associated with stellar rotations. A speculative suggestion is that MPs might be caused by the magnetic brake, a stellar evolutionary effect linked to the rotation. In this work, we use the young massive cluster NGC 419 as a testbed. We examined if its magnetically baked MS stars would exhibit MPs. Using the deep ultraviolet and visible images observed through the Hubble Space Telescope, combined with a specific color index that is sensitive to the nitrogen (N) abundance, we examined if its late G- and K-type MS stars are affected by N variation. Our analysis reports that the morphology of its GK-type MS is most likely an SSP, and only a negligible probability that indicates a N variation up to 0.4 dex is present. We conclude that there is no significant N variation among its GK-type MS stars. The absence of a significant chemical variation among the late-type MS stars indicates that MPs might not be a specific pattern of magnetically braked stars.

[16]  arXiv:2003.00161 [pdf, other]

Title: A Real-time Automatic Validation System for Optical Transients detected by GWAC

Authors: Yang Xu, Liping Xin, Jing Wang, Xuhui Han, Yulei Qiu, Maohai Huang, Jianyan Wei

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

The ground-based wide-angle camera array (GWAC) generates millions of single frame alerts per night. After the complicated and elaborate filters by multiple methods, a couple of dozens of candidates are still needed to be confirmed by follow-up observations in real-time. In order to free scientists from the complex and high-intensity follow-up tasks, we developed a Real-time Automatic transient Validation System (RAVS), and introduce here its system architecture, data processing flow, database schema, automatic follow-up control flow, and mobile message notification solution. This system is capable of automatically carrying out all operations in real-time without human intervention, including the validation of transient candidates, the adaptive light-curve sampling for identified targets in multi-band, and the pushing of observation results to the mobile client. The running of RAVS shows that an M-type stellar flare event can be well sampled by RAVS without a significant loss of the details, while the observing time is only less than one-third of the time coverage. Because the control logic of RAVS is designed to be independent of the telescope hardware, RAVS can be conveniently transplanted to other telescopes, especially the follow-up system of SVOM. Some future improvements are presented for the adaptive light-curve sampling, after taking into account both the brightness of sources and the evolution trends of the corresponding light-curves.

[17]  arXiv:2003.00195 [pdf, other]

Title: Be X-ray binaries in the SMC as (I) indicators of mass transfer efficiency

Authors: Serena Vinciguerra, Coenraad J. Neijssel, Alejandro Vigna-Gómez, Ilya Mandel, Philipp Podsiadlowski, Thomas J. Maccarone, Matt Nicholl, Samuel Kingdon, Alice Perry, Francesco Salemi

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

Be X-ray binaries (BeXRBs) consist of rapidly rotating Be stars with neutron star companions accreting from the circumstellar emission disk. We compare the observed population of BeXRBs in the Small Magellanic Cloud with simulated populations of BeXRB-like systems produced with the COMPAS population synthesis code. We focus on the apparently higher minimal mass of Be stars in BeXRBs than in the Be population at large. Assuming that BeXRBs experienced only dynamically stable mass transfer, their mass distribution suggests that at least $\sim$ 30% of the mass donated by the progenitor of the neutron star is typically accreted by the B-star companion. We expect these results to affect predictions for the population of double compact object mergers. A convolution of the simulated BeXRB population with the star formation history of the Small Magellanic Cloud shows that the excess of BeXRBs is most likely explained by this galaxy's burst of star formation $\sim$ 40 Myr ago, rather than by its low metallicity.

[18]  arXiv:2003.00205 [pdf, ps, other]

Title: The GWAC Data Processing and Management System

Authors: Yang Xu, Liping Xin, Xuhui Han, Hongbo Cai, Lei Huang, Huali Li, Xiaomeng Lu, Yulei Qiu, Chao Wu, Guangwei Li, Jing Wang, Jianyan Wei, Maohai Huang

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

GWAC will have been built an integrated FOV of 5,000 $degree^2$ and have already built 1,800 square $degree^2$. The limit magnitude of a 10-second exposure image in the moonless night is 16R. In each observation night, GWAC produces about 0.7TB of raw data, and the data processing pipeline generates millions of single frame alerts. We describe the GWAC Data Processing and Management System (GPMS), including hardware architecture, database, detection-filtering-validation of transient candidates, data archiving, and user interfaces for the check of transient and the monitor of the system. GPMS combines general technology and software in astronomy and computer field, and use some advanced technologies such as deep learning. Practical results show that GPMS can fully meet the scientific data processing requirement of GWAC. It can online accomplish the detection, filtering and validation of millions of transient candidates, and feedback the final results to the astronomer in real-time. During the observation from October of 2018 to December of 2019, we have already found 102 transients.

[19]  arXiv:2003.00209 [pdf]

Title: An algorithm of selection of meteor candidates in GWAC system

Authors: Yang Xu, Jing Wang, Maohai Huang, Jianyan Wei

Comments: in Chinese

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

With its large field of view, GWAC can record hundreds of meteors every day. These meteors are valuable treasures for some meteor research groups. It is therefore very important to accurately find all of these meteors. To address the challenge of precisely distinguishing meteors from other elongated objects in a GWAC-like sky survey system, we design and implement a meteor candidate recognition algorithm, including the recognizing and morphology analysis of the light curves of the meteor candidates. Although the algorithm may filter out some real meteors, it can provide a sample of meteor with high confidence. After processing the images of Mini-GWAC taken in two months, we detect 109,000 elongated objects in which more than 90 percent of objects are not meteor. Among the elongated objects, about 5.9% objects are identified as meteors with high confidence, after the filters based upon an existence in a single frame, a single peak in the light curves, and a slow variation of the light curves.

[20]  arXiv:2003.00228 [pdf]

Title: Global maps of Venus nightside mean infrared thermal emissions obtained by VIRTIS on Venus Express

Authors: A. Cardesin-Moinelo, G. Piccioni, A. Migliorini, D. Grassi, V. Cottini, D. Titov, R. Politi, F. Nuccilli, P. Drossart

Journal-ref: Icarus Vol. 343, June 2020, 113683

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

One of the striking features about Venus atmosphere is its temporal variability and dynamics, with a chaotic polar vortex, large-scale atmospheric waves, sheared features, and variable winds that depend on local time and possibly orographic features. The aim of this research is to combine data accumulated over several years and obtain a global mean state of the atmosphere focusing in the global structure of the clouds using the cloud opacity and upper cloud temperatures. We have first produced global maps using the integrated radiance through the infrared atmospheric windows centred around 1.74{\mu}m and 2.25{\mu}m, that show the spatial variations of the cloud opacity in the lower clouds around 44-48 km altitude and also provide an indirect estimation of the possible particle size. We have also produced similar global maps using the brightness temperatures seen in the thermal region at 3.8{\mu}m and 5.0{\mu}m, which provide direct indication of the temperatures at the top of the clouds around 60-70 km altitude. These maps have been generated using the complete dataset of the Visible and InfraRed Thermal Imaging Spectrometer mapping channel (VIRTIS-M) on board Venus Express, with a wide spatial and long temporal coverage in the period from May 2006 until October 2008. Our results provide a global view of the cloud opacity, particle size and upper cloud temperatures at both hemispheres, showing the main different dynamical regions of the planet. The profiles obtained also provide the detailed dependencies with latitude, local time and longitude, diagnostic of the global circulation flow and dynamics at various altitude layers, from about 44 up to 70 km over the surface.

[21]  arXiv:2003.00285 [pdf, other]

Title: Linearized model for satellite station-keeping and tandem formations under the effects of atmospheric drag

Authors: David Arnas

Comments: 28 pages, 8 figures

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

This work introduces a linearized analytical model for the study of the dynamic of satellites in near circular orbits under the effects of the atmospheric drag. This includes the evaluation of the station keeping required for each satellite subjected to a control box strategy, and also the study of the dynamic of tandem formations between two or more satellites that are located on the same nominal space-track. The model takes into account the effect of the orbit perturbation provoked by the atmospheric drag, while the effects of the Earth gravitation potential are included in the definition of the nominal orbits of the satellites. This allows to easily define the maneuvering strategies for the satellites involved in the tandem formation and study their absolute and relative dynamic. In particular, this work focuses on the study of a master-slave scenario and the in plane maneuvers that these satellites require. Examples of application of this model are also provided.

[22]  arXiv:2003.00289 [pdf, other]

Title: Interacting galaxies in the IllustrisTNG simulations -- I: Triggered star formation in a cosmological context

Authors: David R. Patton, Kieran D. Wilson, Colin J. Metrow, Sara L. Ellison, Paul Torrey, Westley Brown, Maan H. Hani, Stuart McAlpine, Jorge Moreno, Joanna Woo

Comments: 19 pages, 13 figures. Resubmitted to MNRAS after addressing referee's report

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

We use the IllustrisTNG cosmological hydrodynamical simulations to investigate how the specific star formation rates (sSFRs) of massive galaxies $(M_* > 10^{10} M_\odot)$ depend on the distance to their closest companions. We estimate sSFR enhancements by comparing with control samples that are matched in redshift, stellar mass, local density and isolation, and we restrict our analysis to pairs with stellar mass ratios of 0.1 to 10. At small separations (~15 kpc), the mean sSFR is enhanced by a factor of 2.0 $\pm$ 0.1 in the flagship (110.7 Mpc)$^3$ simulation (TNG100-1). Statistically significant enhancements extend out to 3D separations of 280 kpc in the (302.6 Mpc)$^3$ simulation (TNG300-1). We find similar trends in the EAGLE and Illustris simulations, although their sSFR enhancements are lower than those in TNG100-1 by about a factor of two. Enhancements in IllustrisTNG galaxies are seen throughout the redshift range explored ($0 \leq z < 1$), with the strength of the enhancements decreasing with increasing redshift for galaxies with close companions. In order to more closely compare with observational results, we separately consider 2D projected distances between galaxies in IllustrisTNG. We detect significant sSFR enhancements out to projected separations of 260 kpc in TNG300-1, with projection effects diluting the size of the enhancements by about 20 per cent below 50 kpc. We find similar sSFR enhancements in TNG100-1 and Sloan Digital Sky Survey galaxies, with enhancements extending out to projected separations of about 150 kpc for star-forming galaxies at $z < 0.2$. Finally, by summing over all separations, we estimate that the presence of closest companions boosts the average sSFR of massive galaxies in TNG100-1 by 14.5 per cent.

[23]  arXiv:2003.00375 [pdf, ps, other]

Title: Birth environment of circumbinary planets: are there CBPs on the inclined orbits?

Authors: Chuan-Tao Ma, Yan-Xiang Gong, Xiao-Mei Wu, Jianghui Ji

Comments: Published in MNRAS, vol. 493, p. 1907

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

The inclination distribution of circumbinary planets (CBPs) is an important scientific issue. It is of great significance in estimating the occurrence rate of CBPs and studying their formation and evolution. Although the CBPs currently discovered by the transit method are nearly coplanar, the true inclination distribution of CBPs is still unknown. Previous researches on CBPs mostly regarded them as an isolated binary-planet system, without considering the birth environment of their host binaries. It is generally believed that almost all stars are born in clusters. Therefore, it is necessary to consider the impact of the close encounters of stars on the CBP systems. This article discusses how the close encounters of fly-by stars affect the inclination of CBP. Based on extensive numerical simulations, we found that CBPs in close binary with a spacing of about 0.2 au are almost unaffected by star fly-bys. Their orbits remain coplanar. However, when the spacing of the binary stars is greater than 1 au, the 2-3 fly-bys of the intruding star can excite a considerable inclination even for the CBP near the unstable boundary of the binary. For the planets in the outer region, a single star fly-by can excite an inclination to more than 5 degrees. Especially, CBPs in near polar or retrograde orbits can naturally form through bianry-star encounters. If close binaries are born in open clusters, our simulations suggest that there may be high-inclination CBPs in binaries with spacing > 1 au.

[24]  arXiv:2003.00450 [pdf, ps, other]

Title: Inflation: Are latest detected events of gravitational waves in favor of string theory?

Authors: Basem Ghayour, Jafar Khodagholizadeh, M. Afkani, M. R. Torkamani, Ali Vahedi

Comments: 13 pages, 2 figures

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

The general potential of power-law inflation is as $ V(\phi)\propto \phi^{n} $ with scalar field $\phi$. The behavior of inflation is often known as power-law expansion like $S(\eta)\propto \eta^{1+\beta}$ with $1+\beta<0$. In this paper, the theoretical spectra of relic gravitational waves are compared with the measured strain sensitivity of Advanced LIGO and VIRGO, corresponding to the latest detected events of gravitational waves. The results show tight constraints on $\beta$ and $n$. Also, the obtained constraints indicate that special types of the potential of inflation, prototype, and KKLTI models, which are originated from string theory, are more suitable than other models. Our analysis shows that there exist some more chances for the detection of relic gravitational waves.

[25]  arXiv:2003.00453 [pdf, other]

Title: Physical conditions in two high-redshift H$_2$-bearing GRB-DLAs, 120815A and 121024A

Authors: Gargi Shaw, G. J. Ferland

Comments: 10 pages, 5 figures, 6 tables. Accepted for publication in MNRAS

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

The gamma-ray burst (GRB) afterglows provide an unique opportunity to study the interstellar medium (ISM) of star-forming galaxies at high-redshift. The GRB-DLAs (damped Lyman-$\alpha$ absorbers) contain a large neutral hydrogen column density, N(H I), and are observed against the GRB afterglow. A large fraction of GRB-DLAs show presence of molecular hydrogen (H$_2$) which is an indicator of star-formation. Hence it is important to study those GRB-DLAs which have H$_2$ lines to decipher and understand their physical conditions. The GRB-DLAs 121024A and 120815A, situated at redshift 2.30 and 2.36 respectively, are two such important H$_2$-bearing GRB-DLAs. Besides H$_2$, these two GRB-DLAs also show many metal lines. In this work we have carried out a detail numerical study on the H$_2$ lines, as well as on those metal lines, in GRB-DLAs 121024A and 120815A self-consistently. We use the spectral synthesis code CLOUDY for this study. This modeling helps us to determine the underlying physical conditions which give rise such lines and hence to understand these two GRB-DLAs in much more detail than any other previous investigation. We find that the hydrogen densities for these two H$_2$-bearing DLAs are $\geq$ 60 cm$^{-3}$. Moreover our study infers that the linear sizes are $\leq 17.7$ pc for these two GRB-DLAs, and the mean gas temperatures averaged over the cloud thickness, are $\leq$ 140 K.

[26]  arXiv:2003.00494 [pdf, other]

Title: Model Comparison of $Λ$CDM vs $R_h=ct$ using $H(z)$ measurements

Authors: Guru Sai Haveesh Singirikonda, Shantanu Desai

Comments: 9 pages, 2 figures

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

In 2012, Bilicki and Seikel (arXiv:1206.5130) showed that $H(z)$ data reconstructed using Gaussian Process Regression from cosmic chronometers and BAO, conclusively rules out the $R_h=ct$ model. These results were disputed by Melia and collaborators in two different works (arXiv:1304.1802 and arXiv:1802.02255), who showed using both an unbinned analysis and Gaussian Process reconstructed $H(z)$ data from chronometers, that $R_h=ct$ is favored over $\Lambda$CDM model. To resolve this imbroglio, we carry out model comparison of $\Lambda$CDM versus $R_h=ct$ by independently reproducing the above claims using latest data. We consider $H(z)$ measurements from both cosmic chronometers as well as a combination of chronometers and BAO, and perform model selection between these two models using frequentist, Bayesian, and three different information theoretical criteria. We find that with only cosmic chronometers, no one model is decisively favored. When we combine with BAO data, the information theory and Bayesian model comparison tests decisively favor the $\Lambda$CDM model.

[27]  arXiv:2003.00523 [pdf, ps, other]

Title: Spectral Signatures of Quasar Ages at z~3

Authors: Wei Zheng

Comments: To appear in The Astrophysical Journal, with 22 pages, 10 figures, 3 tables

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

Insight into quasar ages may be obtained from the proximity effect, but so far only in a limited number of bright quasars. Based on ~2600 SDSS quasar spectra at 2.5 <= z <= 3.5, a search for spectral voids between Ly-alpha forest lines finds proximity zones over a wide range of radial distances. The majority of zone sizes are less than 5 Mpc, with their numbers decreasing exponentialy towards larger distances. After normalization by luminosities, the zone sizes are distributed an e-folding scale of 0.64 as compared with the anticipated values. A group of quasars are selected for their large proximity zones of >~ 10 Mpc. Their composite spectrum displays strong narrow cores and large equivalent widths in Ly-alpha and other major UV emission lines. If the proximity zones along lines of sight are indicative of quasar ages, these features may be the signatures of old quasars. Another group of quasars are selected as they show no proximity zone and exhibit intrinsic absorption lines at z_{ab} > z_{em}. They are likely young quasars and exhibit weaker narrow emission-line components. The significant difference of spectral features between the two groups may reflect an evolution pattern over quasars' lifetimes.

[28]  arXiv:2003.00525 [pdf, other]

Title: ALMA Observations of Quasar Host Galaxies at $z\simeq4.8$

Authors: Nathen H. Nguyen, Paulina Lira, Benny Trakhtenbrot, Hagai Netzer, Claudia Cicone, Roberto Maiolino, Ohad Shemmer

Comments: 26 pages, 10 figures, 6 tables. Submitted after Referee review

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

We present ALMA band-7 data of the [CII] $\lambda157.74\,\mu{\rm m}$ emission line and underlying far-infrared (FIR) continuum for twelve luminous quasars at $z \simeq 4.8$, powered by fast-growing supermassive black holes (SMBHs). Our total sample consists of eighteen quasars, twelve of which are presented here for the first time. The new sources consists of six Herschel/SPIRE detected systems, which we define as "FIR-bright" sources, and six Herschel/SPIRE undetected systems, which we define as "FIR-faint" sources. We determine dust masses for the quasars hosts of $M_{dust} \le 0.2-25.0\times 10^8 M_{\odot}$, implying ISM gas masses comparable to the dynamical masses derived from the [CII] kinematics. It is found that on average the MgII line is blueshifted by $\sim 500\,{\rm km\,s}^{-1}$ with respect to the [CII] emission line, which is also observed when complementing our observations with data from the literature. We find that all of our "FIR-bright" subsample and most of the "FIR-faint" objects lie above the main sequence of star forming galaxies at $z \sim 5$. We detect companion sub-millimeter galaxies (SMGs) for two sources, both FIR-faint, with a range of projected distances of $\sim20-60$ kpc and with typical velocity shifts of $\left|\Delta v\right| \lesssim200\,{\rm km\,s}^{-1}$ from the quasar hosts. Of our total sample of eighteen quasars, 5/18 are found to have dust obscured starforming companions.

[29]  arXiv:2003.00536 [pdf, other]

Title: Into the UV: A precise transmission spectrum of HAT-P-41b using Hubble's WFC3/UVIS G280 grism

Authors: H.R. Wakeford, D.K. Sing, K.B. Stevenson, N.K. Lewis, N. Pirzkal, T.J. Wilson, J. Goyal, T. Kataria, T. Mikal-Evans, N. Nikolov, J. Spake

Comments: Accepted to AJ Feb 29, 2020. 20 pages, 17 figures, 3 tables

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

The ultraviolet-visible wavelength range holds critical spectral diagnostics for the chemistry and physics at work in planetary atmospheres. To date, exoplanet time-series atmospheric characterization studies have relied on several combinations of modes on Hubble's STIS/COS instruments to access this wavelength regime. Here for the first time, we apply the Hubble WFC3/UVIS G280 grism mode to obtain exoplanet spectroscopy from 200-800 nm in a single observation. We test the G280 grism mode on the hot Jupiter HAT-P-41b over two consecutive transits to determine its viability for exoplanet atmospheric characterization. We obtain a broadband transit depth precision of 29-33ppm and a precision of on average 200ppm in 10nm spectroscopic bins. Spectral information from the G280 grism can be extracted from both the positive and negative first order spectra, resulting in a 60% increase in the measurable flux. Additionally, the first HST orbit can be fully utilized in the time-series analysis. We present detailed extraction and reduction methods for use by future investigations with this mode, testing multiple techniques. We find the results fully consistent with STIS measurements of HAT-P-41b from 310-800 nm, with the G280 results representing a more observationally efficient and precise spectrum. We fit HAT-P-41b's transmission spectrum with a forward model at Teq=2091K, high metallicity, and significant scattering and cloud opacity. With these first of their kind observations, we demonstrate that WFC3/UVIS G280 is a powerful new tool to obtain UV-optical spectra of exoplanet atmospheres, adding to the UV legacy of Hubble and complementing future observations with the James Webb Space Telescope.

[30]  arXiv:2003.00615 [pdf, ps, other]

Title: PSF--NET: A Non-parametric Point Spread Function Model for Ground Based Optical Telescopes

Authors: Peng Jia, Xuebo Wu, Yi Huang, Bojun Cai, Dongmei Cai

Comments: Accepted by AJ. The complete code can be downloaded at DOI:10.12149/101014

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Solar and Stellar Astrophysics (astro-ph.SR); Computer Vision and Pattern Recognition (cs.CV); Optics (physics.optics)

Ground based optical telescopes are seriously affected by atmospheric turbulence induced aberrations. Understanding properties of these aberrations is important both for instruments design and image restoration methods development. Because the point spread function can reflect performance of the whole optic system, it is appropriate to use the point spread function to describe atmospheric turbulence induced aberrations. Assuming point spread functions induced by the atmospheric turbulence with the same profile belong to the same manifold space, we propose a non-parametric point spread function -- PSF-NET. The PSF-NET has a cycle convolutional neural network structure and is a statistical representation of the manifold space of PSFs induced by the atmospheric turbulence with the same profile. Testing the PSF-NET with simulated and real observation data, we find that a well trained PSF--NET can restore any short exposure images blurred by atmospheric turbulence with the same profile. Besides, we further use the impulse response of the PSF-NET, which can be viewed as the statistical mean PSF, to analyze interpretation properties of the PSF-NET. We find that variations of statistical mean PSFs are caused by variations of the atmospheric turbulence profile: as the difference of the atmospheric turbulence profile increases, the difference between statistical mean PSFs also increases. The PSF-NET proposed in this paper provides a new way to analyze atmospheric turbulence induced aberrations, which would be benefit to develop new observation methods for ground based optical telescopes.

[31]  arXiv:2003.00632 [pdf]

Title: Empirical Photometric Control of Mars Context Camera Images

Authors: Stuart J. Robbins, Michelle R. Kirchoff, Rachael H. Hoover

Comments: 23 pages, 5 figures

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

The Mars Reconnaissance Orbiter (MRO) spacecraft has been in orbit around Mars since March 2006. The Context Camera (CTX) on MRO has returned over 100,000 images of the planet at approximately 5-6 meters per pixel, providing nearly global coverage. During that time, Mars has gone through nearly 7 of its own years, changing solar distance from 1.38 to 1.67 AU and the corresponding solar flux by 45% due to its orbital eccentricity. Seasonal effects and transient phenomena affect atmospheric transparency. Combined with an aging detector, CTX images are difficult to mosaic seamlessly, for all of these changes prevent equalizing images to create a visually smoothly illuminated product. We have developed a method, based on previous work by other researchers for other datasets, to mitigate almost all photometric variations between images in order to create the appearance of an evenly illuminated, practically seamless mosaic. We describe how the process works, which uses a reference source to tie brightness values, and demonstrate its effects across Mars' surface. While the workflow developed for this product is applicable to other planetary bodies, it requires a reference source, which may not yet exist.

[32]  arXiv:2003.00647 [pdf, other]

Title: Improved Constraints on Anisotropic Birefringent Lorentz Invariance and CPT Violation from Broadband Optical Polarimetry of High Redshift Galaxies

Authors: Andrew S. Friedman, Roman Gerasimov, Fabian Kislat, David Leon, Walker Stevens, David Tytler, Brian G. Keating

Comments: 29 pages, 14 figures

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

In the framework of the Standard Model Extension (SME), we present improved constraints on anisotropic Lorentz invariance and Charge-Parity-Time (CPT) violation by searching for astrophysical signals of cosmic vacuum birefringence with broadband optical polarimetry of high redshift astronomical sources, including Active Galactic Nuclei and Gamma-Ray Burst afterglows. We generalize the work in Kislat 2018, which studied the SME mass dimension $d = 4$ case, to arbitrary mass dimension for both the CPT-even and CPT-odd cases. We then present constraints on all 10, 16, and 42 anisotropic birefringent SME coefficients for dimension $d = 4$, $d = 5$, and $d = 6$ models, respectively, using 7554 observations for odd d and 7376 observations for even d of 1278 unique sources on the sky, which, to our knowledge, comprises the most complete catalog of optical polarization from extragalactic sources in the literature to date. Compared to the smaller sample of 44 and 45 broadband optical polarimetry observations analyzed in Kislat 2018 and Kislat and Krawczynski 2017, our dimension $d = 4$ and $d = 5$ average constraints are more sensitive by factors of 35 and 10, corresponding to a reduction in allowed SME parameter space volume for these studies of 15 and 16 orders of magnitude, respectively. Constraints from individual lines of sight can be significantly stronger using spectropolarimetry. Nevertheless, due to the increased number of observations and lines of sight in our catalog, our average $d = 4$ and $d = 5$ broadband constraints are within factors of 2 and 12 of previous constraints using spectropolarimetry from Kislat 2018 and Kislat and Krawczynski 2017, respectively, using an independent data set and an improved analysis method. By contrast, our anisotropic constraints on all 42 birefringent SME coefficients for $d = 6$ are the first to be presented in the literature.

[33]  arXiv:2003.00650 [pdf]

Title: Global Major-Element Maps of Mercury from Four Years of MESSENGER X-Ray Spectrometer Observations

Authors: Larry R. Nittler, Elizabeth A. Frank, Shoshana Z. Weider, Ellen Crapster-Pregont, Audrey Vorburger, Richard D. Starr, Sean C. Solomon

Comments: Accepted for publication by Icarus. 38 pages, 10 figures in main text, plus 6 supplemental figures

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

The X-Ray Spectrometer (XRS) on the MESSENGER spacecraft provided measurements of major-element ratios across Mercury's surface. We present global maps of Mg/Si, Al/Si, S/Si, Ca/Si, and Fe/Si derived from XRS data collected throughout MESSENGER's orbital mission. We describe the procedures we used to select and filter data and to combine them to make the final maps, which are archived in NASA's Planetary Data System. Areal coverage is variable for the different element-ratio maps, with 100% coverage for Mg/Si and Al/Si, but only 18% coverage for Fe/Si north of 30 $^{\circ}$ N, where the spatial resolution is highest. The spatial resolution is improved over previous maps by 10-15% because of the inclusion of higher-resolution data from late in the mission when the spacecraft periapsis altitude was low. Unlike typical planetary data maps, however, the spatial resolution of the XRS maps can vary from pixel to pixel, and thus care must be taken in interpreting small-scale features. We provide several examples of how the XRS maps can be used to investigate elemental variations in the context of geological features on Mercury, which range in size from single $\sim$100-km-diameter craters to large impact basins. We expect that these maps will provide the basis for and/or contribute to studies of Mercury's origin and geological history for many years to come.

[34]  arXiv:2003.00670 [pdf, other]

Title: Evolution of MU69 from a binary planetesimal into contact by Kozai-Lidov oscillations and nebular drag

Authors: Wladimir Lyra, Andrew N. Youdin, Anders Johansen

Comments: 13 pages (main article) + 15 pg appendix; 14 figures. Submitted to Icarus

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

The New Horizons flyby of the cold classical Kuiper Belt object MU69 showed it to be a contact binary. The existence of other contact binaries in the 1-10km range raises the question of how common these bodies are and how they evolved into contact. Here we consider that the lobes of MU69 formed as a binary in the Solar nebula, and calculate its orbital evolution in the presence of gas. We find that the sub-Keplerian wind of the disk brings the drag timescales for 10km bodies under 1 Myr for quadratic-velocity drag. In the Kuiper belt, however, the drag is linear with velocity and the effect of the wind cancels out as the angular momentum gained in half an orbit is lost in the other half: the drag timescales for 10 km bodies remain over 10 Myr. In this situation we find that a combination of drag and Kozai-Lidov oscillations is a promising channel for collapse. We analytically solve the hierarchical three-body problem with drag and implement it into a Kozai plus tidal friction model. The permanent quadrupoles of the lobes make the Kozai oscillations stochastic, and as drag shrinks the semimajor axis it more easily allows the fluctuations to bring the system into contact. Evolution to contact happens very rapidly (within $10^4$ yr) in the pure, double-average quadrupole, Kozai region between $\approx 85-95^\circ$, and within 3 Myr in the drag-assisted region beyond it. The synergy between $J_2$ and gas drag widens the window of contact to 80-100$^\circ$ initial inclination, over a larger range of semimajor axes. As such, the model predicts an initial contact binary fraction of about 10\% for the cold classicals in the Kuiper belt. The speed at contact deviates from the escape velocity only because of the oblateness. For MU69, the contact velocity should be 3.3-4.2 m/s, in line with the observational evidence from the lack of deformation features and estimate of the tensile strength.

[35]  arXiv:2003.00684 [pdf, ps, other]

Title: Longitudinal drift of Tayler instability eigenmodes as a possible explanation for super slowly rotating Ap stars

Authors: L. L. Kitchatinov, I. S. Potravnov, A. A. Nepomnyashchikh

Comments: Submitted to A&A

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

Rotation periods inferred from the magnetic variability of some Ap stars are incredibly long, exceeding ten years in some cases. An explanation for such slow rotation is lacking. This paper attempts an explanation of the super-slow rotation of Ap stars' magnetic and temperature patterns in terms of the longitudinal drift of unstable disturbances of kink-type (Tayler) instability of the stars' internal magnetic field. The rates of drift and growth are computed for eigenmodes of Tayler instability using stellar parameters estimated from a structure model of an A star. The computations refer to the toroidal background magnetic field of variable strength. The non-axisymmetric unstable disturbances drift in counter-rotation direction in the co-rotating reference frame. The drift rate increases with strength of the background field. For a field strength exceeding the (equipartition) value of equal Alfven and rotational velocities, the drift rate approaches the proper rotation rate of a star. The eigenmodes in an inertial frame show very slow rotation in this case. Patterns of magnetic and thermal disturbances of the slowly rotating eigenmodes are also computed. The counter-rotational drift of Tayler instability eigenmodes is a possible explanation for the observed phenomenon of super-slowly rotating Ap stars.

[36]  arXiv:2003.00685 [pdf, other]

Title: The Multi-INstrument Burst ARchive (MINBAR)

Authors: D. K. Galloway (1), J. J. M. in 't Zand (2), J. Chenevez (3), H. Wörpel (4), L. Keek (5), L. Ootes (6), A. L. Watts (6), L. Gisler (1), C. Sanchez-Fernandez (7), E. Kuulkers (8) ((1) Monash University, (2) SRON, (3) DTU Space, (4) AIP Potsdam, (5) University of Maryland, (6) University of Amsterdam, (7) ESAC, Madrid (8) ESTEC, Noordwijk)

Comments: 108 pages, 34 figures, 18 tables; machine-readable sample data tables available via this https URL; web interface to sample data available via this http URL Submitted to ApJS

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

We present the largest sample of type-I (thermonuclear) X-ray bursts yet assembled, comprising 7083 bursts from 85 bursting sources. The sample is drawn from observations with Xenon-filled proportional counters on the long-duration satellites RXTE, BeppoSAX and INTEGRAL, between 1996 February 8, and 2012 May 3. We assembled a catalog of 113 burst sources, from which the sample burst sources are drawn. We carried out a consistent analysis for each burst lightcurve (normalised to the relative instrumental effective area), and provide measurements of rise time, peak intensity, exponential decay timescale, burst \tau-value, and fluence. For bursts observed with the RXTE/PCA and BeppoSAX/WFC we also provide time-resolved spectroscopy, including estimates of bolometric peak flux and fluence, and spectral parameters at the peak of the burst. For 950 bursts observed with the PCA from sources with previously detected burst oscillations, we include an analysis of the high-time resolution data, providing information on the detectability and amplitude of the oscillations, as well as where in the burst they are found. We also present analysis of 117883 observations of the burst sources within the sample timeframe. We extracted 3-25 keV X-ray spectra from most observations, and (for observations meeting our signal-to-noise criterion), we provide measurements of the flux, spectral colours, and for selected sources, the position on the colour-colour diagram, for the best-fit spectral model. We present a description of the sample, a summary of the science investigations completed to date, and suggestions for further studies.

[37]  arXiv:2003.00693 [pdf, ps, other]

Title: Gravitational waves from slow combustion of a neutron star to quark star

Authors: Shailendra Singh, Ritam Mallick, R Prasad

Comments: 17 pages, 8 figures

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

Fluctuation at the neutron star center gives rise to a small deconfined quark core very close to the star center. The density discontinuity at the quark-hadron boundary initiates a shock wave, which propagates outwards of the star. The shock is strong enough to combust nuclear matter to 2-flavor quark matter in the star. The 2-flavor quark matter is not stable and there is an excess of down quarks. The 2-flavor matter settles to a stable 3-flavor matter in the weakly interacting time-scale. In this paper particularly study the conversion of 2-flavor matter to 3-flavor matter is carried out. We set up a differential equation for the conversion of the excess of down quarks to strange quarks involving weak reaction and diffusion of quarks. Calculating the reaction rate we solve the differential equation to find the velocity of the conversion front. The conversion velocity is about $0.002$ times of the speed of light and the time taken for the conversion is about $1.96$ millisecond. Once the front velocity is known we find the change in density profile of the star. As the conversion front moves out of the star the density profile changes bringing about a change in the quadrupole moment of the star. The change in the quadrupole moment is reflected in the GW amplitude which is of the order of $10^{-24}-10^{-23}$. The power spectrum has a peak frequencies of around $10-20$ kHz. Such amplitude and peak frequency is a unique signature of shock-induced first-order phase transition.

[38]  arXiv:2003.00709 [pdf, other]

Title: The Infrared Medium-deep Survey. \Romannum{7}. Faint Quasars at $z \sim 5$ in the ELAIS-N1 Field

Authors: Suhyun Shin, Myungshin Im, Yongjung Kim, Minhee Hyun, Soojong Pak, Yiseul Jeon, Tae-Geun Ji, Hojae Ahn, Seoyeon Byeon, Jimin Han, Sungyong Hwang, Sophia Kim, Gu Lim, Insu Paek, Gregory S. H. Paek, Yoon Chan Taak, Changsu Choi, Jueun Hong, Hyunsung David Jun, Dohyeong Kim, Duho Kim, Minjin Kim, Jae-Woo Kim, Ji Hoon Kim, Hye-In Lee, Seong-Kook Lee, Won-Kee Park, Woojin Park, Yongmin Yoon

Comments: 16 pages, 9 figures, 4 tables. Accepted for publication in ApJ

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

The intergalactic medium (IGM) at $z\sim$ 5 to 6 is largely ionized, and yet the main source for the IGM ionization in the early universe is uncertain. Of the possible contributors are faint quasars with $-26 \lesssim M_{\rm 1450} \lesssim -23$, but their number density is poorly constrained at $z\sim5$. In this paper, we present our survey of faint quasars at $z\sim5$ in the European Large-Area {\it ISO} Survey-North 1 (ELAIS-N1) field over a survey area of 6.51 deg$^2$ and examine if such quasars can be the dominant source of the IGM ionization. We use the deep optical/near-infrared data of the ELAIS-N1 field as well as the additional medium-band observations to find $z \sim 5$ quasars through a two-step approach using the broadband color selection, and SED fitting with the medium-band information included. Adopting Bayesian information criterion, we identify ten promising quasar candidates. Spectra of three of the candidates are obtained, confirming all of them to be quasars at $z\sim5$ and supporting the reliability of the quasar selection. Using the promising candidates, we derive the $z\sim5$ quasar luminosity function at $-26 \lesssim M_{\rm 1450} \lesssim -23$. The number density of faint $z\sim5$ quasars in the ELAIS-N1 field is consistent with several previous results that quasars are not the main contributors to the IGM-ionizing photons at $z\sim5$

[39]  arXiv:2003.00720 [pdf, other]

Title: AARTFAAC discovery of extreme-fluence pulses from PSR B0950+08

Authors: Mark J. Kuiack, Ralph A.M.J. Wijers, Antonia Rowlinson, Aleksandar Shulevski, Folkert Huizinga, Gijs Molenaar, Peeyush Prasad

Comments: 10 pages, 9 figure, 1 table. Submitted to MNRAS

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

Here we report on the detection of extreme-fluence pulses (EFP) from PSR B0950+08 with the Amsterdam-Astron Radio Transient Facility And Analysis Center (AARTFAAC), a parallel transient detection instrument operating as a subsystem of the LOw Frequency ARray (LOFAR). During processing of our Northern Hemisphere survey for low frequency (58.3 and 61.8 MHz) radio transients, a sample of 275 pulses with fluences ranging from 42k to 177k Jy ms were detected in one-second snapshot images. The brightest pulses are more than two orders of magnitude brighter than those previously reported at 42 and 74 MHz. Although the power-law pulse-energy distribution index agrees well with the previous results, the average rate of EFPs is much higher. Given the number of EFPs observed, and the power-law index of the pulse-fluence distribution at high fluence, a single power-law cannot be extended to the typical pulse population. Activity was found to be highly variable, with only two three-hour observations accounting for nearly half of the pulses detected in the 96 hours surveyed. The rate of EFPs varied from 0 to 30 detected per hour between consecutive days of observation. However, no clustering was observed within a single active three-hour span. The spectra appear intrinsically structured with narrow band emission, confined, at times, within 195.3 kHz sub-bands, and dynamic, with the pulse spectra changing on timescale of $\sim$10 minutes. This narrow emission bandwidth provides strong evidence that the EFPs are intrinsically higher energy, rather than being magnified by propagation effects.

[40]  arXiv:2003.00721 [pdf, other]

Title: SKIRT 9: redesigning an advanced dust radiative transfer code to allow kinematics, line transfer and polarization by aligned dust grains

Authors: Peter Camps, Maarten Baes

Comments: 24 pages, 14 figures, accepted for publication in Astronomy and Computing

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

The open source SKIRT Monte Carlo radiative transfer code has been used for more than 15 years to model the interaction between radiation and dust in various astrophysical systems. In this work, we present version 9 of the code, which has been substantially redesigned to support long-term objectives. We invite interested readers to participate in the development, testing and application of new features such as including gas media types in addition to dust, performing line transfer in addition to continuum radiation transfer, and modeling polarization by non-spherical dust grains aligned by magnetic fields. We describe the major challenges involved in preparing the code for these and other extensions, as well as their resolution, including a completely new treatment of wavelengths to support kinematics. SKIRT 9 properly runs over 400 handcrafted functional tests and successfully performs all relevant benchmarks. The source code and all documentation is publicly available for use and ready for further collaborative development.

[41]  arXiv:2003.00743 [pdf, other]

Title: The disk of 2MASS 15491331-3539118 = GQ Lup C as seen by HST and WISE

Authors: C. Lazzoni, R. Gratton, J.M. Alcalà, S. Desidera, A. Frasca, C.F. Manara, D. Mesa, E. Rigliaco, A. Vigan, A. Zurlo

Comments: 5 pages, 4 figures

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

Very recently, a second companion on wider orbit has been discovered around GQ Lup. This is a low-mass accreting star partially obscured by a disk seen at high inclination. If detected, this disk may be compared to the known disk around the primary. We detected this disk on archive HST and WISE data. The extended spectral energy distribution provided by these data confirms the presence of accretion from Halpha emission and UV excess, and shows an IR excess attributable to a warm disk. In addition, we resolved the disk on the HST images. This is found to be roughly aligned with the disk of the primary. Both of them are roughly aligned with the Lupus I dust filament containing GQ Lup.

[42]  arXiv:2003.00795 [pdf, other]

Title: Two-temperature Magnetohydrodynamic simulations for sub-relativistic AGN jets:Dependence on the fraction of the electron heating

Authors: T. Ohmura, M. Machida, K.E. Nakamura, Y.Kudoh, R. Matsumoto

Comments: 13 pages, 12 figures, accepted for publication in MNRAS

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

We present the results of two-temperature magnetohydrodynamic simulations of the propagation of sub-relativistic jets of active galactic nuclei. The dependence of the electron and ion temperature distributions on the fraction of electron heating fe at the shock front is studied for fe=0, 0.05, and 0.2. Numerical results indicate that in sub-relativistic, rarefied jets, the jet plasma crossing the terminal shock forms a hot, two-temperature plasma in which the ion temperature is higher than the electron temperature. The two-temperature plasma expands and forms a backflow referred to as a cocoon, in which the ion temperature remains higher than the electron temperature for longer than 100 Myr. Electrons in the cocoon are continuously heated by ions through Coulomb collisions, and the electron temperature thus remains at Te > 10^9 K in the cocoon. X-ray emissions from the cocoon are weak because the electron number density is low. Meanwhile, soft X-rays are emitted from the shocked intracluster medium surrounding the cocoon. Mixing of the jet plasma and the shocked intracluster medium through the Kelvin--Helmholtz instability at the interface enhances X-ray emissions around the contact discontinuity between the cocoon and shocked intracluster medium.

[43]  arXiv:2003.00927 [pdf, ps, other]

Title: Extension of the synchrotron radiation of electrons to very high energies in clumpy environments

Authors: Dmitry Khangulyan, Felix Aharonian, Carlo Romoli, Andrew Taylor

Comments: 6 pages, 4 figures

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

The synchrotron cooling of relativistic electrons is one of the most effective radiation mechanisms in astrophysics. It not only accompanies the process of particle acceleration but also has feedback on the formation of the energy distribution of the parent electrons. The radiative cooling time of electrons decreases with energy as $t_{\rm syn} \propto 1/E$; correspondingly the overall radiation efficiency increases with energy. On the other hand, this effect strictly limits the maximum energy of individual photons. Even in the so-called extreme accelerators, where the acceleration proceeds at the highest possible rate, $t_{\rm acc} = E/eBc$, the synchrotron radiation cannot extend well beyond the characteristic energy determined by the electron mass and the fine-structure constant: $h \nu_{\rm max} \sim m_e c^2/\alpha \sim 100 \rm\,MeV$. In a highly turbulent medium with a broad magnetic field distribution, this limit is shifted towards higher energies. However, for any realistic distribution of the magnetic field, it cannot significantly exceed $ h \nu_{\rm max}$. In this paper, we propose a model in which the formation of synchrotron radiation takes place in compact magnetic blobs located inside the particle accelerator. We develop a formalism for calculations of synchrotron radiation emerging from such systems. We demonstrate that for certain combinations of parameters characterizing the accelerator and the magnetic blobs, the synchrotron radiation can extend into the very high energy (VHE) domain, $h \nu_{\rm max} \geq 100 \ \rm GeV$. We briefly outline the possible astrophysical implications of the results in the context of VHE radiation of blazars and gamma-ray bursts.

[44]  arXiv:2003.00969 [pdf, other]

Title: Searching for Fast Neutrino Flavor Conversion Modes in Core-collapse Supernova Simulations

Authors: Sajad Abbar

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

Neutrinos propagating in dense neutrino media such as those in core-collapse supernovae can experience fast flavor conversions on scales much shorter than those expected in vacuum. It is believed that a necessary condition for the occurrence of fast modes is that the angular distributions of $\nu_e$ and $\bar\nu_e$ cross each other. However, most of the state-of-the-art supernova simulations do not provide such detailed angular information and instead, consider only a few moments of neutrino angular distributions. We here propose an efficient method to use these available few moments to search for fast modes in supernova simulations. Our method, which is based on searching for crossings in the angular distributions, can work with any number of moments provided by the simulation though a larger number of crossings can be captured when higher moments are available.

[45]  arXiv:2003.00972 [pdf, other]

Title: Core-collapse supernova explosions driven by the hadron-quark phase transition as rare $r$ process site

Authors: Tobias Fischer, Meng-Ru Wu, Benjamin Wehmeyer, Niels-Uwe F. Bastian, Gabriel Martínez-Pinedo, Friedrich-Karl Thielemann

Comments: 14 pages, 7 figures, submitted to The Astrophysical Journal

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

Supernova explosions of massive stars are one of the primary sites for the production of the elements in the universe. Up to now, stars with zero-age main sequence masses in the range of 35-50 M$_\odot$ had mostly been representing the failed supernova explosion branch. Contrarily, it has been demonstrated recently that the appearance of exotic phases of hot and dense matter, associated with a sufficiently strong phase transition from nuclear matter to the quark-gluon plasma at high baryon density, can trigger supernova explosions of such massive supergiant stars (Fischer et al. 2018). Here, we present the first results obtained from an extensive nucleosynthesis analysis for material being ejected from the surface of the newly born proto-neutron star of such supernova explosions. These ejecta contain an early neutron-rich component and a late-time high-entropy neutrino-driven wind. The nucleosynthesis robustly overcomes the production of nuclei associated with the second $r$-process peak, at nuclear mass number $A\simeq 130$, and proceeds beyond the formation of the 3$^{\rm rd}$ peak ($A\simeq 195$) to the actinides. These yields may account for metal-poor star observations concerning $r$-process elements such as strontium and europium in the galaxy at low metallcity, while the actinide yields suggests that this source may be a candidate contributing to the abundances of radioactive $^{244}$Pu measured in deep-sea sediments on Earth.

[46]  arXiv:2003.00983 [pdf, ps, other]

Title: Analytical determination of the structure and nuclear abundances of the outer crust of a cold nonaccreted neutron star

Authors: Nicolas Chamel

Comments: 15 pages. Accepted for publication in Physical Review C

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

A very fast iterative method is presented to calculate the internal constitution of the outer crust of a cold nonaccreted neutron star, making use of very accurate analytical formulas for the transition pressures between adjacent crustal layers and their density. In addition to the composition of the different crustal layers, their depth and their baryonic mass content can be simultaneously estimated using an approximate solution of Einstein's general relativistic equations. The overall computing time is drastically reduced compared to the traditional approach, thus opening the door to large-scale statistical studies and sensitivity analyses.

[47]  arXiv:2003.00984 [pdf, ps, other]

Title: The UV surface habitability of Proxima b: first experiments revealing probable life survival to stellar flares

Authors: Ximena C. Abrevaya, Martin Leitzinger, Oscar oppezzo, Petra Odert, Manish Patel, Gerardo J. M. Luna, Ana F. Forte-Giacobone, Arnold Hanslmeier

Comments: Accepted for publication in MNRAS Letters

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

We use a new interdisciplinary approach to study the UV surface habitability of Proxima $b$ under quiescent and flaring stellar conditions. We assumed planetary atmospheric compositions based on CO$_2$ and N$_2$ and surface pressures from 100 to 5000 mbar. Our results show that the combination of these atmospheric compositions and pressures provide enough shielding from the most damaging UV wavelengths, expanding the "UV-protective" planetary atmospheric compositions beyond ozone. Additionally, we show that the UV radiation reaching the surface of Proxima $b$ during quiescent conditions would be negligible from the biological point of view, even without an atmosphere. Given that high UV fluxes could challenge the existence of life, then, we experimentally tested the effect that flares would have on microorganisms in a "worst-case scenario" (no UV-shielding). Our results show the impact that a typical flare and a superflare would have on life: when microorganisms receive very high fluences of UVC, such as those expected to reach the surface of Proxima $b$ after a typical flare or a superflare, a fraction of the population is able to survive. Our study suggests that life could cope with highly UV irradiated environments in exoplanets under conditions that cannot be found on Earth.

[48]  arXiv:2003.00986 [pdf, other]

Title: Stochastic Calibration of Radio Interferometers

Authors: Sarod Yatawatta

Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Artificial Intelligence (cs.AI); Distributed, Parallel, and Cluster Computing (cs.DC)

With ever increasing data rates produced by modern radio telescopes like LOFAR and future telescopes like the SKA, many data processing steps are overwhelmed by the amount of data that needs to be handled using limited compute resources. Calibration is one such operation that dominates the overall data processing computational cost, nonetheless, it is an essential operation to reach many science goals. Calibration algorithms do exist that scale well with the number of stations of an array and the number of directions being calibrated. However, the remaining bottleneck is the raw data volume, which scales with the number of baselines, and which is proportional to the square of the number of stations. We propose a 'stochastic' calibration strategy where we only read in a mini-batch of data for obtaining calibration solutions, as opposed to reading the full batch of data being calibrated. Nonetheless, we obtain solutions that are valid for the full batch of data. Normally, data need to be averaged before calibration is performed to accommodate the data in size-limited compute memory. Stochastic calibration overcomes the need for data averaging before any calibration can be performed, and offers many advantages including: enabling the mitigation of faint radio frequency interference; better removal of strong celestial sources from the data; and better detection and spatial localization of fast radio transients.

[49]  arXiv:2003.01012 [pdf, other]

Title: A rapid change in X-ray variability and a jet ejection in the black hole transient MAXI J1820+070

Authors: Jeroen Homan, Joe Bright, Sara E. Motta, Diego Altamirano, Zaven Arzoumanian, Arkadip Basak, Tomaso M. Belloni, Edward M. Cackett, Rob Fender, Keith C. Gendreau, Erin Kara, Dheeraj R. Pasham, Ronald A. Remillard, James F. Steiner, Abigail L. Stevens, Phil Uttley

Comments: Accepted for publication in ApJ Letters

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

We present Neutron Star Interior Composition Explorer X-ray and Arcminute Microkelvin Imager Large Array radio observations of a rapid hard-to-soft state transition in the black hole X-ray transient MAXI J1820+070. During the transition from the hard state to the soft state a switch between two particular types of quasiperiodic oscillations (QPOs) was seen in the X-ray power density spectra, from type-C to type-B, along with a drop in the strength of the broadband X-ray variability and a brief flare in the 7-12 keV band. Soon after this switch (~1.5-2.5 hr) a strong radio flare was observed that corresponded to the launch of superluminal ejecta. Although hints of a connection between QPO transitions and radio flares have been seen in other black hole X-ray transients, our observations constitute the strongest observational evidence to date for a link between the appearance of type-B QPOs and the launch of discrete jet ejections.

[50]  arXiv:2003.01046 [pdf, other]

Title: First germanium-based constraints on sub-MeV Dark Matter with the EDELWEISS experiment

Authors: EDELWEISS Collaboration: Q. Arnaud, E. Armengaud, C. Augier, A. Benoît, L. Bergé, J. Billard, A. Broniatowski, P. Camus, A. Cazes, M. Chapellier, F. Charlieux, M. De Jésus, L. Dumoulin, K. Eitel, E. Elkhoury, J.-B. Fillipini, D. Filosofov, J. Gascon, A. Giuliani, M. Gros, Y. Jin, A. Juillard, M. Kleifges, H. Lattaud, S. Marnieros, D. Misiak, X.-F. Navick, C. Nones, E. Olivieri, C. Oriol, P. Pari, B. Paul, D. Poda, S. Rozov, T. Salagnac, V. Sanglard, B. Siebenborn, L. Vagneron, M. Weber, E. Yakushev, A. Zolotarova

Comments: 6 pages, 4 figures

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

The EDELWEISS collaboration has performed a search for Dark Matter (DM) particles interacting with electrons using a 33.4 g Ge cryogenic detector operated underground at the LSM. A charge resolution of 0.53 electron-hole pairs (RMS) has been achieved using the Neganov-Trofimov-Luke amplification with a bias of 78 V. We set the first Ge-based constraints on sub-MeV/c$^{2}$ DM particles interacting with electrons, as well as on dark photons down to 1 eV/c$^2$. These are competitive with other searches. In particular, new limits are set on the kinetic mixing of dark photon DM in a so far unconstrained parameter space region in the 6 to 9 eV/c$^2$ mass range. These results demonstrate the high relevance of cryogenic Ge detectors for the search of DM interactions producing eV-scale electron signals.

[51]  arXiv:2003.01047 [pdf, other]

Title: Blending and obscuration in weak lensing magnification

Authors: E.Gaztanaga, S.J.Schmidt, M.D.Schneider, J.A.Tyson

Comments: 13 pages, 11 Fig., submitted to MNRAS

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

We test the impact of some systematic errors in weak lensing magnification measurements with the COSMOS 30-band photo-$z$ Survey flux limited to $i_{AB}<25.0$ using correlations of both source galaxy counts and fluxes. Systematic obscuration effects are measured by comparing counts and flux correlations. We use the ACS-HST catalogs to identify potential blending objects (close pairs) and perform the magnification analyses with and without blended objects. We find that blending effects start to be important ($\sim$ 0.04~mag obscuration) at angular scales smaller than 0.1 arcmin. Extinction and other systematic obscuration effects can be as large as 0.10~mag (U-band) but are typically smaller than 0.02~mag depending on the band. After applying these corrections, we measure a $3.9\sigma$ magnification signal that is consistent for both counts and flux magnification. The corresponding projected mass profiles of galaxies at redshift $z \simeq 0.6$ ($M_I \simeq -21$) is $\Sigma= 25\pm 6 M_{sun}h^3/pc^2$ at 0.1 Mpc/h, consistent with NFW type profile with $M_{200} \simeq 2 \times 10^{12} M_{sun} h/pc^2$. Tangential shear and flux-size magnification over the same lenses show similar mass profiles. We conclude that magnification from counts and fluxes using photometric redshifts has the potential to provide complementary weak lensing information in future wide field surveys once we carefully take into account systematic effects, such as obscuration and blending.

[52]  arXiv:2003.01071 [pdf, other]

Title: A census of the pulsar population observed with the international LOFAR station FR606 at low frequencies (25-80~MHz)

Authors: L. Bondonneau, J.-M. Grießmeier, G. Theureau, A. V. Bilous, V. I. Kondratiev, M. Serylak, M. J. Keith, A. G. Lyne

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

To date, only 69 pulsars have been identified with a detected pulsed radio emission below 100 MHz. A LOFAR-core LBA census and a dedicated campaign with the Nan\c{c}ay LOFAR station in stand-alone mode were carried out in the years 2014$-$2017 in order to extend the known population in this frequency range. In this paper, we aim to extend the sample of known radio pulsars at low frequencies and to produce a catalogue in the frequency range of 25-80 MHz. This will allow future studies to probe the local Galactic pulsar population, in addition to helping explain their emission mechanism, better characterising the low-frequency turnover in their spectra, and obtaining new information about the interstellar medium through the study of dispersion, scattering, and scintillation. We observed 102 pulsars that are known to emit radio pulses below 200 MHz and with declination above \SI{-30}{\degree}. We used the the Low Band Antennas (LBA) of the LOw Frequency ARray (LOFAR) international station FR606 at the Nan\c{c}ay Radio Observatory in stand-alone mode, recording data between 25-80 MHz. complemented with a few additional candidates. Out of our sample of 102 pulsars, we detected 64. We confirmed the existence of ten pulsars detected below 100 MHz by the LOFAR LBA census for the first time \citep{bilous_lofar_2019} and we added two more pulsars that had never before been detected in this frequency range. We provided average pulse profiles, DM values, and mean flux densities (or upper limits in the case of non-detections). The comparison with previously published results allows us to identify a hitherto unknown spectral turnover for five pulsars, confirming the expectation that spectral turnovers are a widespread phenomenon.

[53]  arXiv:2003.01083 [pdf, other]

Title: An extremely powerful long-lived superluminal ejection from the black hole MAXI J1820+070

Authors: J. S. Bright, R. P. Fender, S. E. Motta, D. R. A. Williams, J. Moldon, R. M. Plotkin, J. C. A. Miller-Jones, I. Heywood, E. Tremou, R. Beswick, G. R. Sivakoff, S. Corbel, D. A. H. Buckley, J. Homan, E. Gallo, A. J. Tetarenko, T. D. Russell, D. A. Green, D. Titterington, P. A. Woudt, R. P. Armstrong, P. J. Groot, A. Horesh, A. J. van der Horst, E. G. Körding, V. A. McBride, A. Rowlinson, R. A. M. J. Wijers

Comments: 57 pages, 8 figures, published in Nature Astronomy

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

Black holes in binary systems execute patterns of outburst activity where two characteristic X-ray states are associated with different behaviours observed at radio wavelengths. The hard state is associated with radio emission indicative of a continuously replenished, collimated, relativistic jet, whereas the soft state is rarely associated with radio emission, and never continuously, implying the absence of a quasi-steady jet. Here we report radio observations of the black hole transient MAXI J1820$+$070 during its 2018 outburst. As the black hole transitioned from the hard to soft state we observed an isolated radio flare, which, using high angular resolution radio observations, we connect with the launch of bi-polar relativistic ejecta. This flare occurs as the radio emission of the core jet is suppressed by a factor of over 800. We monitor the evolution of the ejecta over 200 days and to a maximum separation of 10$''$, during which period it remains detectable due to in-situ particle acceleration. Using simultaneous radio observations sensitive to different angular scales we calculate an accurate estimate of energy content of the approaching ejection. This energy estimate is far larger than that derived from state transition radio flare, suggesting a systematic underestimate of jet energetics.

[54]  arXiv:2003.01099 [pdf, other]

Title: Suppression of scalar power on large scales and associated bispectra

Authors: H. V. Ragavendra, Debika Chowdhury, L. Sriramkumar

Comments: 16 pages, 11 figures

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

A sharp cut-off in the primordial scalar power spectrum on large scales has been known to improve the fit to the cosmic microwave background data when compared to the more standard, nearly scale invariant power spectrum that arises in slow roll inflation. In a recent work, we had numerically investigated the characteristics of the scalar bispectrum generated in models with kinetically dominated initial conditions. In this work, we compare the scenario with two other competing scenarios (viz. punctuated inflation and a model due to Starobinsky) which also suppress the scalar power in a roughly similar fashion on large scales. We further consider two other scenarios involving inflation of a finite duration, one wherein the scalar field begins on the inflationary attractor and another wherein the field starts with a smaller velocity and evolves towards the attractor. These scenarios too exhibit a sharp drop in power on large scales if the initial conditions on the perturbations for a range of modes are imposed on super-Hubble scales as in the kinetically dominated model. The model wherein the background field always remains on the inflationary attractor is interesting for the reason that it permits analytical calculations of the scalar power and bispectra. We compare the amplitudes and shapes of the scalar non-Gaussianity parameter $f_{_{\rm NL}}$ in all these cases which lead to scalar power spectra of similar form. Interestingly, we find that, in the models wherein the initial conditions on the perturbations are imposed on super-Hubble scales, the consistency relation governing the scalar bispectrum is violated for the large scale modes, whereas the relation is satisfied for all the modes in the other scenarios. These differences in the behavior of the scalar bispectra can conceivably help us observationally discriminate between the various models which lead to similar power spectra.

Cross-lists for Tue, 3 Mar 20

[55]  arXiv:2002.12628 (cross-list from gr-qc) [pdf, ps, other]

Title: Numerical simulation of sky localization for LISA-TAIJI joint observation

Authors: Gang Wang, Wei-Tou Ni, Wen-Biao Han, Shu-Cheng Yang, Xing-Yu Zhong

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA); Instrumentation and Methods for Astrophysics (astro-ph.IM)

LISA is considered to be launched alongside the Athena to probe the energetic astrophysical processes. LISA can determine the direction of sources for Athena's follow-up observation. As another space gravitational wave mission, TAIJI is expected to be launched in the 2030s. The LISA-TAIJI network would provide abundant merits for sources understanding. In this work, we simulate the joint LISA-TAIJI observations for gravitational waves from coalescing supermassive black hole binaries and monochromatic sources. By using the numerical mission orbits, we evaluate the performances of sky localization for various time-delay interferometry channels. For 30 days observation until coalescence, the LISA-TAIJI network in optimal operation can localize all simulated binary sources, $(10^7,\ 3.3 \times 10^6)\ M_\odot$, $(10^6,\ 3.3 \times 10^5)\ M_\odot$ and $(10^5,\ 3.3 \times 10^4)\ M_\odot$ at redshift $z=2$, in 0.4 deg$^2$ (field of view of Wide Field Imager on Athena). The angular resolution can be improved by more than 10 times comparing to LISA or TAIJI single detector at a given percentage of population. The improvements for monochromatic sources at 3 mHz and 10 mHz are relatively moderate in one-year observation. The precision of sky localization could be improved by around 1 to 3 times comparing to single LISA at a given percentage of sources. For a simulated 90 days observation for monochromatic waves, the LISA-TAIJI network still represents a considerable localization advantage which could be more than 10 times better.

[56]  arXiv:2003.00021 (cross-list from hep-ph) [pdf, other]

Title: Systematizing the Effective Theory of Self-Interacting Dark Matter

Authors: Prateek Agrawal, Aditya Parikh, Matthew Reece

Comments: 22 pages, 6 figures

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

If dark matter has strong self-interactions, future astrophysical and cosmological observations, together with a clearer understanding of baryonic feedback effects, might be used to extract the velocity dependence of the dark matter scattering rate. To interpret such data, we should understand what predictions for this quantity are made by various models of the underlying particle nature of dark matter. In this paper, we systematically compute this function for fermionic dark matter with light bosonic mediators of vector, scalar, axial vector, and pseudoscalar type. We do this by matching to the nonrelativistic effective theory of self-interacting dark matter and then computing the spin-averaged viscosity cross section nonperturbatively by solving the Schrodinger equation, thus accounting for any possible Sommerfeld enhancement of the low-velocity cross section. In the pseudoscalar case, this requires a coupled-channel analysis of different angular momentum modes. We find, contrary to some earlier analyses, that nonrelativistic effects only provide a significant enhancement for the cases of light scalar and vector mediators. Scattering from light pseudoscalar and axial vector mediators is well described by tree-level quantum field theory.

[57]  arXiv:2003.00026 (cross-list from physics.flu-dyn) [pdf, other]

Title: Convective dynamics with mixed temperature boundary conditions: why thermal relaxation matters and how to accelerate it

Authors: Evan H. Anders, Geoffrey M. Vasil, Benjamin P. Brown, Lydia Korre

Comments: Submitted to Physical Review Fluids. 15 pages including references with 6 figures, 2 tables, and 1 appendix

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

Astrophysical simulations of convection frequently impose different thermal boundary conditions at the top and the bottom of the domain in an effort to more accurately reflect the natural system being modeled. In this work, we study Rayleigh-B\'enard convection (RBC) with mixed (``FT'') temperature boundary conditions. We aim to understand how FT boundaries change the nature of the convective solution compared to the traditional choice of fixing the temperature at the top and bottom of the domain (``TT''). We find that simulations with FT boundaries experience a long thermal rundown while simulations with TT boundaries do not. In the relaxed state, the mean behavior of an FT simulation corresponds to an equivalent simulation with TT boundaries. The fast evolution of TT simulations can therefore be taken advantage of to rapidly relax FT simulations. We show that these findings carry over to more complicated problems through a brief examination of rotating convection. We furthermore find that FT boundaries introduce minor asymmetries into the flow fields, with the fixed flux boundary producing more extreme events than the fixed temperature boundary, but that these asymmetries do not appreciably affect the bulk flows. We conclude that thermal relaxation occurs in two stages: (1) changes to the experimental energy reservoir and (2) changes to the stratification of the experiment. Through the proper choice of boundary conditions or initial conditions, the first of these stages can be bypassed, and the second stage seems to be irrelevant for RBC.

[58]  arXiv:2003.00072 (cross-list from gr-qc) [pdf, ps, other]

Title: Directed searches for continuous gravitational waves from twelve supernova remnants in data from Advanced LIGO's second observing run

Authors: Lee Lindblom, Benjamin J. Owen

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

We describe directed searches for continuous gravitational waves from twelve well localized non-pulsing candidate neutron stars in young supernova remnants using data from Advanced LIGO's second observing run. We assumed that each neutron star is isolated and searched a band of frequencies from 15 to 150\,Hz, consistent with frequencies expected from known young pulsars. After coherently integrating spans of data ranging from 12.0 to 55.9 days using the F-statistic and applying data-based vetoes, we found no evidence of astrophysical signals. We set upper limits on intrinsic gravitational wave amplitude in some cases stronger than 10^{-25}, generally about a factor of two better than upper limits on the same objects from Advanced LIGO's first observing run.

[59]  arXiv:2003.00099 (cross-list from hep-ph) [pdf, other]

Title: $CP$ violation from $τ$, $t$ and $b$ dimension-6 Yukawa couplings -- interplay of baryogenesis, EDM and Higgs physics

Authors: Elina Fuchs, Marta Losada, Yosef Nir, Yehonatan Viernik

Comments: 20 pages + appendix, 5 figures, 3 tables

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

We explore the implications of the Standard Model effective field theory (SMEFT) with dimension-six terms involving the Higgs boson and third-generation fermion fields on the rate of Higgs boson production and decay into fermions, on the electric dipole moments (EDMs) of the electron, and on the baryon asymmetry of the Universe. We study the consequences of allowing these additional terms for each flavor separately and for combinations of two flavors. We find that a complex $\tau$ Yukawa coupling can account for the observed baryon asymmetry $Y_B^{\rm obs}$ within current LHC and EDM bounds. A complex $b$ ($t$) Yukawa coupling can account for $4\%$ ($2\%$) of $Y_B^{\rm obs}$, whereas a combination of the two can reach $12\%$. Combining $\tau$ with either $t$ or $b$ enlarges the viable parameter space owing to cancellations in the EDM and in either Higgs production times decay or the total Higgs width, respectively. Interestingly, in such a scenario there exists a region in parameter space where the SMEFT contributions to the electron EDM cancel and collider signal strengths are precisely SM-like, while producing sufficient baryon asymmetry. Measuring $CP$ violation in Higgs decays to $\tau$ leptons is the smoking gun for this scenario.

[60]  arXiv:2003.00101 (cross-list from hep-ph) [pdf, ps, other]

Title: Reply to Robinson and Michaud, arXiv:2002.08893

Authors: Noah Kurinsky, Daniel Baxter, Yonatan Kahn, Gordan Krnjaic, Peter Abbamonte

Comments: 4 Pages

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Materials Science (cond-mat.mtrl-sci); High Energy Physics - Experiment (hep-ex); Instrumentation and Detectors (physics.ins-det)

We respond to Robinson and Michaud's (RM) comment (arXiv:2002.08893) on our recent preprint arXiv:2002.06937, in which we discuss recent excesses in low-threshold dark matter searches, and offer a potential unifying dark matter interpretation. We thank RM for their feedback, which highlights the critical need for future measurements to directly calibrate plasmon charge yields for low $\sim$ 10 eV energy depositions. RM objected to our assertion that plasmons generated at energy scales below 100~eV may have a large branching fraction into phonons. As we argue below, the points raised by RM do not invalidate our primary conclusions, as they pertain to a much different energy scale than we discuss in our paper.

[61]  arXiv:2003.00121 (cross-list from physics.atom-ph) [pdf, ps, other]

Title: Large-scale multiconfiguration Dirac-Hartree-Fock calculations for astrophysics: n=4 levels in P-like ions from Mn~XI to Ni~XIV

Authors: C. X. Song, K. Wang, G. Del Zanna, P. Jönsson, R. Si, M. Godefroid, G. Gaigalas, L. Radži{ū}t{ė}, P. Rynkun, X. H. Zhao, J. Yan, C. Y. Chen

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

Using the multiconfiguration Dirac-Hartree-Fock and the relativistic configuration interaction methods, a consistent set of transition energies and radiative transition data for the lowest 546 (623, 701, 745) states of the $3p^4 3d$, $3s 3p^2 3d^2$, $3s 3p^3 4p$, $3s 3p^4$, $3s^2 3d^3$, $3s^2 3p^2 3d$, $3s^2 3p^2 4d$, $3s^2 3p^2 4s$, $3p^3 3d^2$, $3p^5$, $3s 3p 3d^3$, $3s 3p^3 3d$, $3s 3p^3 4s$, $3s^2 3p 3d^2$, %$3s^2 3p^2 4f$, $3s^2 3p^2 4p$, $3s^2 3p^3$ configurations in Mn~XI (Fe~XII, Co~XIII, Ni~XIV) is provided. The comparison between calculated excitation energies for the $n=4$ states and available experimental values for Fe XII indicate that the calculations are highly accurate, with uncertainties of only a few hundred cm$^{-1}$. Lines from these states are prominent in the soft X-rays. With the present calculations, several recent new identifications are confirmed. Other identifications involving $3p^2 4d$ levels in Fe~XII that were found questionable are discussed and a few new assignments are recommended. As some $n=4$ states of the other ions also show large discrepancies between experimental and calculated energies, we reassess their identification. The present study provides highly accurate atomic data for the $n=4$ states of P-like ions of astrophysical interest, for which experimental data are scarce.

[62]  arXiv:2003.00286 (cross-list from gr-qc) [pdf, other]

Title: Probing Einstein-dilaton Gauss-Bonnet Gravity with the inspiral and ringdown of gravitational waves

Authors: Zack Carson, Kent Yagi

Comments: 12 pages, 4 figures

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

Gravitational waves from extreme gravity events such as the coalescence of two black holes in a binary system fill our observable universe, bearing with them the underlying theory of gravity driving their process. One compelling alternative theory of gravity -- known as Einstein-dilaton Gauss-Bonnet gravity motivated by string theory -- describes the presence of an additional dilaton scalar field coupled directly to higher orders of the curvature, effectively describing a "fifth force" interaction and the emission of scalar dipole radiation between two scalarized black holes. Most previous studies focused on considering only the leading correction to the inspiral portion of the binary black hole waveforms. In our recent paper, we carried out inspiral-merger-ringdown consistency tests in this string-inspired gravity by including corrections to both the inspiral and ringdown portions, as well as those to the mass and spin of remnant black holes, valid to quadratic order in spin. We here extend the analysis by directly computing bounds on the theoretical coupling constant using the full inspiral-merger-ringdown waveform rather than treating the inspiral and merger-ringdown portions separately. We also consider the corrections valid to quartic order in spin to justify the validity of black hole's slow-rotation approximation. We find the quasinormal mode corrections to the waveform to be particularly important for high-mass events such as GW170729, in which the dilaton fields' small-coupling approximation fails without such effects included. We also show that future space-based and multiband gravitational-wave observations have the potential to go beyond existing bounds on the theory. The bounds presented here are comparable to those found in via the inspiral-merger-ringdown consistency tests.

[63]  arXiv:2003.00357 (cross-list from gr-qc) [pdf, other]

Title: Exploring the Bayesian parameter estimation of binary black holes with LISA

Authors: Sylvain Marsat, John G. Baker, Tito Dal Canton

Comments: 34 pages, 18 figures

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

The space-based gravitational wave detector LISA will observe mergers of massive black hole binary systems (MBHBs) to cosmological distances, as well as inspiralling stellar-origin (or stellar-mass) binaries (SBHBs) years before they enter the LIGO/Virgo band. Much remains to be explored for the parameter recovery of both classes of systems. Previous MBHB analyses relied on inspiral-only signals and/or a simplified Fisher matrix analysis, while SBHBs have not yet been extensively analyzed with Bayesian methods. We accelerate likelihood computations by (i) using a Fourier-domain response of the LISA instrument, (ii) using a reduced-order model for non-spinning waveforms that include a merger-ringdown and higher harmonics, (iii) setting the noise realization to zero and computing overlaps in the amplitude/phase representation. We present the first simulations of Bayesian inference for the parameters of massive black hole systems including consistently the merger and ringdown of the signal, as well as higher harmonics. We clarify the roles of LISA response time and frequency dependencies in breaking degeneracies and illustrate how degeneracy breaking unfolds over time. We also find that restricting the merger-dominated signal to its dominant harmonic can make the extrinsic likelihood very degenerate. Including higher harmonics proves to be crucial to break degeneracies and considerably improves the localization of the source, with a surviving bimodality in the sky position. We also present simulations of Bayesian inference for the extrinsic parameters of SBHBs, and show that although unimodal, their posterior distributions can have non-Gaussian features.

[64]  arXiv:2003.00477 (cross-list from gr-qc) [pdf, other]

Title: Shadow and Quasinormal Modes of a Rotating Loop Quantum Black Hole

Authors: Cheng Liu, Tao Zhu, Qiang Wu, Kimet Jusufi, Mubasher Jamil, Mustapha Azreg-Aïnou, Anzhong Wang

Comments: 21 pages, 12 figures

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

In this paper, we construct an effective rotating loop quantum black hole (LQBH) solution, starting from the spherical symmetric LQBH by applying the Newman-Janis algorithm modified by Azreg-A\"{i}nou's non-complexification procedure, and study the effects of loop quantum gravity (LQG) on its shadow. Given the rotating LQBH, we discuss its horizon, ergosurface, and regularity as $r \to 0$. Depending on the values of the specific angular momentum $a$ and the polymeric function $P$ arising from LQG, we find that the rotating solution we obtained can represent a regular black hole, a regular extreme black hole, or a regular spacetime without horizon (a non-black-hole solution). We also study the effects of LQG and rotation and show that, in addition to the specific angular momentum, the polymeric function also causes deformations in the size and shape of the black hole shadow. Interestingly, for a given value of $a$ and inclination angle $\theta_0$, the apparent size of the shadow monotonically decreases, and the shadow gets more distorted with increasing $P$. We also consider the effects of $P$ on the deviations from the circularity of the shadow and find that the deviation from circularity increases with increasing $P$ for fixed values of $a$ and $\theta_0$. Additionally, we explore the observational implications of $P$ in comparing with the latest Event Horizon Telescope (EHT) observation of the supermassive black hole, M$87$. The connection between the shadow radius and quasinormal modes in the eikonal limit as well as the deflection of massive particles are also considered.

[65]  arXiv:2003.00629 (cross-list from hep-th) [pdf, other]

Title: Non-Gaussianities and tensor-to-scalar ratio in non-local R^2-like inflation

Authors: Alexey S. Koshelev, K. Sravan Kumar, Anupam Mazumdar, Alexei A. Starobinsky

Comments: 38 pages, 6 figures

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

In this paper we will study $R^2$-like inflation in a non-local modification of gravity which contains quadratic in Ricci scalar and Weyl tensor terms with analytic infinite derivative form-factors in the action. It is known that the inflationary solution of the local $R+R^2$ gravity remains a particular exact solution in this model. It was shown earlier that the power spectrum of scalar perturbations generated during inflation in the non-local setup remains the same as in the local $R+R^2$ inflation, whereas the power spectrum of tensor perturbations gets modified due to the non-local Weyl tensor squared term. In the present paper we go beyond 2-point correlators and compute the non-Gaussian parameter $f_{NL}$ related to 3-point correlations generated during inflation, which we found to be different from those in the original local inflationary model and scenarios alike based on a local gravity. We evaluate non-local corrections to the scalar bi-spectrum which give non-zero contributions to squeezed, equilateral and orthogonal onfigurations. We show that $f_{NL}\sim O(1)$ with an arbitrary sign is achievable in this model based on the choice of form-factors and the scale of non-locality. We present the predictions for the tensor-to-scalar ratio, $r$, and the tensor tilt, $n_t$. In contrast to standard inflation in a local gravity, here the possibility $n_t$>0 is not excluded. Thus, future CMB data can probe non-local behaviour of gravity at high space-time curvatures.

[66]  arXiv:2003.00664 (cross-list from hep-th) [pdf, other]

Title: Consistent inflationary cosmology from quadratic gravity with dynamical torsion

Authors: Katsuki Aoki, Shinji Mukohyama

Comments: 28 pages, 5 figures

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

The idea of gauge theories of gravity predicts that there should exist not only the massless graviton but also massive particles carrying the gravitational force. We study the cosmology in a quadratic gravity with dynamical torsion where gravity may be interpreted as a gauge force associated with the Poincar\'{e} group. In addition to the massless spin-2 graviton, the model contains four non-ghost massive particle species: a couple of spin-0, a spin-1 and a spin-2. Supposing the restoration of the local Weyl invariance in the UV limit and the parity invariance, we find the most general minisuperspace action describing a homogeneous and isotropic universe with a flat spatial geometry. We then transform the minisuperspace action to a quasi-Einstein frame in which the field space is a hyperboloid and the field potential is a combination of those of a Starobinsky-like inflation and a natural inflation. Remarkably, thanks to the multi-field dynamics, the Starobinsky-like inflationary trajectory can be realized even if the initial condition is away from the top of the Starobinsky-like potential. We also study linear tensor perturbations and find qualitatively different features than the Starobinsky inflation, spontaneous parity violation and mixing of the massless and massive spin-2 modes, which might reveal the underlying nature of gravity through inflationary observables.

[67]  arXiv:2003.00763 (cross-list from hep-ph) [pdf, other]

Title: Chirality transfer & chiral turbulence in gauge theories

Authors: M. Mace, N. Mueller, S. Schlichting, S. Sharma

Comments: Quark Matter 2019 conference proceeding

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

Chirality transfer between fermions and gauge fields plays a crucial role for understanding the dynamics of anomalous transport phenomena such as the Chiral Magnetic Effect. In this proceeding we present a first principles study of these processes based on classical-statistical real-time lattice simulations of strongly coupled QED $(e^2N_f=64)$. Our simulations demonstrate that a chirality imbalance in the fermion sector triggers chiral plasma instabilities in the gauge field sector, which ultimately lead to the generation of long range helical magnetic fields via a self-similar turbulent cascade of the magnetic helicity.

[68]  arXiv:2003.01100 (cross-list from hep-ph) [pdf, other]

Title: The landscape of QCD axion models

Authors: Luca Di Luzio, Maurizio Giannotti, Enrico Nardi, Luca Visinelli

Comments: Review article for Physics Report. 142 pages. Instructions to submit comments and signalling missing references are given in the front page

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

We review the landscape of QCD axion models. Theoretical constructions that extend the window for the axion mass and couplings beyond conventional regions are highlighted and classified. Bounds from cosmology, astrophysics and experimental searches are reexamined and updated.

Replacements for Tue, 3 Mar 20

[69]  arXiv:1501.06570 (replaced) [pdf, other]

Title: Superradiance -- the 2020 Edition

Authors: Richard Brito, Vitor Cardoso, Paolo Pani

Comments: 277 pages. Second Edition of the "Lecture Notes in Physics" book by Springer-Verlag. Overall improvement, typos and incorrect statements of Edition 1 are now corrected; new sections were added, reflecting activity in the field. Bounds on ultralight fields are summarized in Table 4, and updated online regularly at this https URL and this https URL

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

[70]  arXiv:1808.01740 (replaced) [pdf, ps, other]

Title: Apparent evidence for Hawking points in the CMB Sky

Authors: Daniel An, Krzysztof A. Meissner, Pawel Nurowski, Roger Penrose

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

[71]  arXiv:1808.02472 (replaced) [pdf, other]

Title: Ups and Downs in Dark Energy: phase transition in dark sector as a proposal to lessen cosmological tensions

Authors: Abdolali Banihashemi, Nima Khosravi, Amir H. Shirazi

Comments: 10 pages, 8 figures, 1 table. CMB dataset is included

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

[72]  arXiv:1808.06848 (replaced) [pdf, other]

Title: Constraining the Neutron Star Radius with Joint Gravitational-Wave and Short Gamma-Ray Burst Observations of Neutron Star-Black Hole Coalescing Binaries

Authors: Stefano Ascenzi, Nicola De Lillo, Carl-Johan Haster, Frank Ohme, Francesco Pannarale

Comments: Published in The Astrophysical Journal, Volume 877, Issue 2, article id. 94, 13 pp. (2019)

Journal-ref: The Astrophysical Journal, Volume 877, Issue 2, article id. 94, 13 pp. (2019)

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

[73]  arXiv:1810.00164 (replaced) [pdf, other]

Title: A new probe of gravity: strongly lensed gravitational wave multi-messenger approach

Authors: Tao Yang, Bin Hu, Rong-Gen Cai, Bin Wang

Comments: match to the published version

Journal-ref: The Astrophysical Journal, Volume 880, Number 1, 2019

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

[74]  arXiv:1901.06561 (replaced) [pdf, other]

Title: Cylindrical Systems in General Relativity

Authors: K. Bronnikov, N. O. Santos, Anzhong Wang

Comments: revote-4, 1 table and 8 figures. Some typos are corrected. Version to appear in Class. Quantum Grav

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

[75]  arXiv:1902.08374 (replaced) [pdf, other]

Title: Constraints of general screened modified gravities from comprehensive analysis of binary pulsars

Authors: Xing Zhang, Wen Zhao, Tan Liu, Kai Lin, Chao Zhang, Xiang Zhao, Shaojun Zhang, Tao Zhu, Anzhong Wang

Comments: 14 pages, 20 figures, 2 tables, ApJ874 (2019) 121 (11pages)

Journal-ref: Astrophys. J. 874 (2019) 121

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

[76]  arXiv:1903.04843 (replaced) [pdf, other]

Title: Probing GHz Gravitational Waves with Graviton-magnon Resonance

Authors: Asuka Ito, Tomonori Ikeda, Kentaro Miuchi, Jiro Soda

Comments: 5 pages, 1 figure, minor changes

Journal-ref: Eur. Phys. J. C 80, 179 (2020)

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

[77]  arXiv:1903.07382 (replaced) [pdf, other]

Title: Background dynamics of pre-inflationary scenario in Brans-Dicke loop quantum cosmology

Authors: Manabendra Sharma, Tao Zhu, Anzhong Wang

Comments: 18 pages, 8 figures, 1 table. Published in Commun. Theor. Phys. 71 (2019) 1205-1218

Journal-ref: Commun. Theor. Phys. 71 (2019) 1205-1218

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); High Energy Physics - Theory (hep-th)

[78]  arXiv:1905.05776 (replaced) [pdf, other]

Title: Light Dark Matter from Inelastic Cosmic Ray Collisions

Authors: James Alvey, Miguel Campos, Malcolm Fairbairn, Tevong You

Comments: 6 pages, 4 figures, v2 published in PRL

Journal-ref: Phys. Rev. Lett. 123, 261802 (2019)

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

[79]  arXiv:1906.00242 (replaced) [pdf, other]

Title: The early growth of supermassive black holes in cosmological hydrodynamic simulations with constrained Gaussian realizations

Authors: Kuan-Wei Huang, Yu Feng, Tiziana Di Matteo

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

[80]  arXiv:1906.10788 (replaced) [pdf, ps, other]

Title: Response of SDO/HMI observables to heating of the solar atmosphere by precipitating high-energy electrons

Authors: Viacheslav M Sadykov, Alexander G Kosovichev, Irina N Kitiashvili, Graham S Kerr

Comments: 24 pages, 5 figures. Accepted to ApJ

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

[81]  arXiv:1907.00355 (replaced) [pdf, ps, other]

Title: Analysis of the duration$-$hardness ratio plane of gamma-ray bursts with skewed distributions

Authors: Mariusz Tarnopolski

Comments: Proceedings of the 12th INTEGRAL conference and 1st AHEAD Gamma-ray Workshop, Geneva (Switzerland), 11-15 February 2019, Ed. C. Ferrigno, E. Bozzo, P. von Balmoos

Journal-ref: Memorie della Societa Astronomica Italiana, 90 (2019) 45-48

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

[82]  arXiv:1907.04346 (replaced) [pdf, other]

Title: Strongly interacting dark sectors in the early Universe and at the LHC through a simplified portal

Authors: Elias Bernreuther, Felix Kahlhoefer, Michael Krämer, Patrick Tunney

Comments: 28 pages, 8 figures; v2 matches published version

Journal-ref: JHEP 2001 (2020) 162

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

[83]  arXiv:1908.02439 (replaced) [pdf, other]

Title: Variability of massive stars in M31 from the Palomar Transient Factory

Authors: Monika D. Soraisam, Lars Bildsten, Maria R. Drout, Thomas A. Prince, Thomas Kupfer, Frank Masci, Russ R. Laher, Shrinivas R. Kulkarni

Comments: 20 pages + Appendix, accepted to ApJ

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

[84]  arXiv:1908.09918 (replaced) [pdf, other]

Title: Search for PeV Gamma-Ray Emission from the Southern Hemisphere with 5 Years of Data from the IceCube Observatory

Authors: 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, M. Börner, 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. (293 additional authors not shown)

Comments: 22 pages, 16 figures

Journal-ref: The Astrophysical Journal, 891:9 (16pp), 2020 March 1

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

[85]  arXiv:1908.10861 (replaced) [pdf, other]

Title: Absorption of Fermionic Dark Matter by Nuclear Targets

Authors: Jeff A. Dror, Gilly Elor, Robert McGehee

Comments: 30 pages plus appendices, 8 figures, 3 tables. v2: published in JHEP with minor revisions (no change to results)

Journal-ref: JHEP 2002 (2020) 134

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

[86]  arXiv:1910.01205 (replaced) [pdf, other]

Title: Chiral Anomaly, Schwinger Effect, Euler-Heisenberg Lagrangian, and application to axion inflation

Authors: Valerie Domcke, Yohei Ema, Kyohei Mukaida

Comments: 45 pages, 9 figures; v2: typos fixed, published version

Journal-ref: JHEP 2002 (2020) 055

Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); High Energy Physics - Theory (hep-th)

[87]  arXiv:1910.05331 (replaced) [pdf, other]

Title: 2-OGC: Open Gravitational-wave Catalog of binary mergers from analysis of public Advanced LIGO and Virgo data

Authors: Alexander H. Nitz, Thomas Dent, Gareth S. Davies, Sumit Kumar, Collin D. Capano, Ian Harry, Simone Mozzon, Laura Nuttall, Andrew Lundgren, Márton Tápai

Comments: 14 pages, 4 Figures, 4 tables, supplemental materials at this https URL, updated to match version accepted by ApJ

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

[88]  arXiv:1910.05767 (replaced) [pdf, ps, other]

Title: Speed of sound constraints on maximally rotating neutron stars

Authors: Ch. Margaritis, P.S. Koliogiannis, Ch.C. Moustakidis

Comments: v1: 8 pages, 10 figures, 2 tables. v2: 10 pages, 15 figures, 3 tables; sections, tables, figures and references had been added. v3: 12 pages, 10 figures, 5 tables; accepted for publication in Phy. Rev. D

Journal-ref: Phys. Rev. D 101, 043023 (2020)

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

[89]  arXiv:1910.08366 (replaced) [pdf, other]

Title: Intensity interferometry of P Cygni in the H$α$ emission line: towards distance calibration of LBV supergiant stars

Authors: J.-P. Rivet, A. Siciak, E. S. G. de Almeida, F. Vakili, A. Domiciano de Souza, M. Fouché, O. Lai, D. Vernet, R. Kaiser, W. Guerin

Comments: To be published in MNRAS

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

[90]  arXiv:1910.11627 (replaced) [pdf, other]

Title: Interpreting High-Resolution Spectroscopy of Exoplanets Using Cross-Correlations and Supervised Machine Learning

Authors: Chloe Fisher, H. Jens Hoeijmakers, Daniel Kitzmann, Pablo Márquez-Neila, Simon L. Grimm, Raphael Sznitman, Kevin Heng

Comments: 15 pages, 18 figures

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

[91]  arXiv:1911.00088 (replaced) [pdf, other]

Title: O$(d,d)$ covariant String Cosmology to all orders in $α^{\prime}$

Authors: Heliudson Bernardo, Robert Brandenberger, Guilherme Franzmann

Comments: 27 pages, 1 figure

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

[92]  arXiv:1911.00199 (replaced) [pdf, other]

Title: String Gases and the Swampland

Authors: Samuel Laliberte, Robert Brandenberger

Comments: This is a new version of our original work. In this new version, we clarified some confusing statements, added a few comments, fixed typos and included a few citations relevant to the initial paper

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

[93]  arXiv:1911.00263 (replaced) [pdf, ps, other]

Title: A new method to test the cosmic distance duality relation using the strongly lensed gravitational waves

Authors: Hai-Nan Lin, Xin Li

Comments: 6 pages, 0 figure and 0 table, accepted by Chinese Physics C

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

[94]  arXiv:1911.01197 (replaced) [pdf, other]

Title: On the Jet Production Efficiency in a Sample of the Youngest Radio Galaxies

Authors: A. Wójtowicz, Ł. Stawarz, C.C. Cheung, L. Ostorero, E. Kosmaczewski, A. Siemiginowska

Comments: the Astrophysical Journal, in press

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

[95]  arXiv:1912.02173 (replaced) [pdf, ps, other]

Title: Black Hole Genesis and origin of cosmic acceleration

Authors: Nikodem J. Popławski

Comments: 4 pages

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

[96]  arXiv:1912.02622 (replaced) [pdf, other]

Title: Science Case for the Einstein Telescope

Authors: Michele Maggiore, Chris van den Broeck, Nicola Bartolo, Enis Belgacem, Daniele Bertacca, Marie Anne Bizouard, Marica Branchesi, Sebastien Clesse, Stefano Foffa, Juan García-Bellido, Stefan Grimm, Jan Harms, Tanja Hinderer, Sabino Matarrese, Cristiano Palomba, Marco Peloso, Angelo Ricciardone, Mairi Sakellariadou

Comments: 51 pages, 14 figures; v3: references added, various improvements. Version accepted in JCAP

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

[97]  arXiv:1912.04272 (replaced) [pdf, other]

Title: Broadband, millimeter-wave antireflection coatings for large-format, cryogenic aluminum oxide optics

Authors: A. Nadolski, J. D. Vieira, J. A. Sobrin, A. M. Kofman, P. A. R. Ade, Z. Ahmed, A. J. Anderson, J. S. Avva, R. Basu Thakur, A. N. Bender, B. A. Benson, L. Bryant, J. E. Carlstrom, F. W. Carter, T. W. Cecil, C. L. Chang, J. R. Cheshire IV, G. E. Chesmore, J. F. Cliche, A. Cukierman, T. de Haan, M. Dierickx, J. Ding, D. Dutcher, W. Everett, J. Farwick, K. R. Ferguson, L. Florez, A. Foster, J. Fu, J. Gallicchio, A. E. Gambrel, R. W. Gardner, J. C. Groh, S. Guns, R. Guyser, N. W. Halverson, A. H. Harke-Hosemann, N. L. Harrington, R. J. Harris, J. W. Henning, W. L. Holzapfel, D. Howe, N. Huang, K. D. Irwin, O. Jeong, M. Jonas, A. Jones, M. Korman, J. Kovac, D. L. Kubik, S. Kuhlmann, C.-L. Kuo, A. T. Lee, A. E. Lowitz, J. McMahon, J. Meier, S. S. Meyer, D. Michalik, J. Montgomery, T. Natoli, H. Nguyen, et al. (27 additional authors not shown)

Comments: 19 pages, 11 figures; submitted 05 Dec 2019, accepted 26 Feb 2020

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

[98]  arXiv:1912.04509 (replaced) [pdf, ps, other]

Title: Formation rate of LB-1-like systems through dynamical interactions

Authors: Ataru Tanikawa, Tomoya Kinugawa, Jun Kumamoto, Michiko S. Fujii

Comments: 9 pages, 1 figure, accepted for publication in PASJ

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

[99]  arXiv:1912.07300 (replaced) [pdf, other]

Title: Gas Density Perturbations in Cool Cores of CLASH Galaxy Clusters

Authors: Shutaro Ueda, Yuto Ichinohe, Sandor M. Molnar, Keiichi Umetsu, Tetsu Kitayama

Comments: 30 pages, 8 figures, accepted for publication in ApJ

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

[100]  arXiv:1912.07924 (replaced) [pdf, other]

Title: Relativistic SZ temperature scaling relations of groups and clusters derived from the BAHAMAS and MACSIS simulations

Authors: Elizabeth Lee, Jens Chluba, Scott T. Kay, David J. Barnes

Comments: Accepted by MNRAS

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

[101]  arXiv:2001.01746 (replaced) [pdf, other]

Title: The Orbital Histories of Magellanic Satellites Using Gaia DR2 Proper Motions

Authors: Ekta Patel, Nitya Kallivayalil, Nicolas Garavito-Camargo, Gurtina Besla, Daniel R. Weisz, Roeland P. van der Marel, Michael Boylan-Kolchin, Marcel S. Pawlowski, Facundo A. Gómez

Comments: 32 pages, 11 figures. Accepted to ApJ

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

[102]  arXiv:2001.08543 (replaced) [pdf, other]

Title: Testing MSW effect in Supernova Explosion with Neutrino event rates

Authors: Kwang-Chang Lai, C. S. Jason Leung, Guey-Lin Lin

Comments: 17 pages, 7 figures

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

[103]  arXiv:2001.10968 (replaced) [pdf, ps, other]

Title: XMM-Newton observations of a gamma-ray pulsar J0633+0632: pulsations, cooling and large-scale emission

Authors: Andrey Danilenko, Anna Karpova, Dmitry Ofengeim, Yury Shibanov, Dmitry Zyuzin

Comments: 15 pages, 10 figures, 5 tables

Journal-ref: 2020, Monthly Notices of the Royal Astronomical Society, Volume 493, Issue 2, p.1874-1887

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

[104]  arXiv:2002.10364 (replaced) [pdf, ps, other]

Title: Revisiting the 2PN pericentre precession in view of possible future measurements of it

Authors: Lorenzo Iorio

Comments: Latex2e, 24 pages, 2 figures, no tables. Typos corrected in Eq.(2) and in Eq.(57). Conclusions unchanged

Subjects: General Relativity and Quantum Cosmology (gr-qc); Earth and Planetary Astrophysics (astro-ph.EP); Space Physics (physics.space-ph)

[105]  arXiv:2002.12574 (replaced) [pdf, other]

Title: A multi-wavelength view of the open cluster NGC 2527: Discovery of active stars

Authors: Nevil Shah, K. P. Singh, Annapurni Subramaniam

Comments: Accepted for publication in MNRAS

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

[106]  arXiv:2002.12775 (replaced) [pdf, other]

Title: NuSTAR observations of G11.2-0.3

Authors: K. K. Madsen, C. L. Fryer, B. W. Grefenstette, L. A. Lopez, S. Reynolds, A. Zoglauer

Journal-ref: ApJ, 2020, 889, 23

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

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