We gratefully acknowledge support from
the Simons Foundation and Leiden University.

Astrophysics

New submissions

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New submissions for Mon, 13 Apr 20

[1]  arXiv:2004.04747 [pdf, other]
Title: Evolution of the Thermodynamic Properties of Clusters of Galaxies out to Redshift of 1.8
Comments: 29 pages, 12 figures, 6 tables, submitted to ApJ
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

The thermodynamic properties of the hot plasma in galaxy clusters retains information on the processes leading to the formation and evolution of the gas in their deep, dark matter potential wells. These processes are dictated not only by gravity but also by gas physics, e.g. AGN feedback and turbulence. In this work, we study the thermodynamic properties, e.g. density, temperature, pressure, and entropy, of the most massive and the most distant ($z > 1.2$) SPT-selected clusters, and compare them with those of the nearby clusters ($z<0.1$) to constrain their evolution as a function of time and radius. We find that thermodynamic properties in the outskirts of high redshift clusters are remarkably similar to the low redshift clusters, and their evolution follows the prediction of the self-similar model. Their intrinsic scatter is larger, indicating that the physical properties that lead to the formation and virialization of cluster outskirts show evolving variance. On the other hand, thermodynamic properties in the cluster cores deviates significantly from self-similarity indicating that the processes that regulate the core are already in place in these very high redshift clusters. This result is supported by the unevolving physical scatter of all thermodynamic quantities in cluster cores.

[2]  arXiv:2004.04748 [pdf, other]
Title: Modelling thermochemical processes in protoplanetary disks I: numerical methods
Comments: MNRAS accepted
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

The dispersal phase of planet-forming disks via winds driven by irradiation from the central star and/or magnetic fields in the disk itself is likely to play an important role in the formation and evolution of planetary systems. Current theoretical models lack predictive power to adequately constrain observations. We present PRIZMO, a code for evolving thermochemistry in protoplanetary disks capable of being coupled with hydrodynamical and multi-frequency radiative transfer codes. We describe the main features of the code, including gas and surface chemistry, photochemistry, microphysics, and the main cooling and heating processes. The results of a suite of benchmarks, which include photon-dominated regions, slabs illuminated by radiation spectra that include X-ray, and well-established cooling functions evaluated at different temperatures show good agreement both in terms of chemical and thermal structures. The development of this code is an important step to perform quantitative spectroscopy of disk winds, and ultimately the calculation of line profiles, which is urgently needed to shed light on the nature of observed disk winds.

[3]  arXiv:2004.04749 [pdf, other]
Title: Multi-phase outflows in post starburst E+A galaxies -- II. A direct connection between the neutral and ionized outflow phases
Comments: MNRAS accepted
Subjects: Astrophysics of Galaxies (astro-ph.GA)

Post starburst E+A galaxies are systems that hosted a powerful starburst that was quenched abruptly. Simulations suggest that these systems provide the missing link between major merger ULIRGs and red and dead ellipticals, where AGN feedback is responsible for the expulsion or destruction of the molecular gas. However, many details remain unresolved and little is known about AGN-driven winds in this short-lived phase. We present spatially-resolved IFU spectroscopy with MUSE/VLT of SDSS J124754.95-033738.6, a post starburst E+A galaxy with a recent starburst that started 70 Myrs ago and ended 30 Myrs ago, with a peak SFR of $\sim 150\,\mathrm{M_{\odot}/yr}$. We detect disturbed gas throughout the entire field of view, suggesting triggering by a minor merger. We detect fast-moving multi-phased gas clouds, embedded in a double-cone face-on outflow, which are traced by ionized emission lines and neutral NaID \emph{emission} and absorption lines. We find remarkable similarities between the kinematics, spatial extents, and line luminosities of the ionized and neutral gas phases, and propose a model in which they are part of the same outflowing clouds, which are exposed to both stellar and AGN radiation. Our photoionization model provides consistent ionized line ratios, NaID absorption optical depths and EWs, and dust reddening. Using the model, we estimate, for the first time, the neutral-to-ionized gas mass ratio (about 20), the sodium neutral fraction, and the size of the outflowing clouds. This is one of the best ever observed direct connections between the neutral and ionized outflow phases in AGN.

[4]  arXiv:2004.04753 [pdf, other]
Title: Mon-735: A new low-mass pre-main sequence eclipsing binary in NGC 2264
Comments: 18 pages, 14 figures, 5 tables, accepted for publication in MNRAS
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP); Astrophysics of Galaxies (astro-ph.GA)

We present Mon-735, a detached double-lined eclipsing binary (EB) member of the $\sim$3 Myr old NGC 2264 star forming region, detected by Spitzer. We simultaneously model the Spitzer light curves, follow-up Keck/HIRES radial velocities, and the system's spectral energy distribution to determine self-consistent masses, radii and effective temperatures for both stars. We find that Mon-735 comprises two pre-main sequence M dwarfs with component masses of $M = 0.2918 \pm 0.0099$ and $0.2661 \pm 0.0095$ $\rm{M}_{\odot}$, radii of $R = 0.762 \pm 0.022$ and $0.748 \pm 0.023$ $\rm{R}_{\odot}$, and effective temperatures of $T_{\rm eff} = 3260 \pm 73$ and $3213 \pm 73$ $\rm{K}$. The two stars travel on circular orbits around their common centre of mass in $P = 1.9751388 \pm 0.0000050$ days. We compare our results for Mon-735, along with another EB in NGC 2264 (CoRoT 223992193), to the predictions of five stellar evolution models. These suggest that the lower mass EB system Mon-735 is older than CoRoT 223992193 in the mass-radius diagram (MRD) and, to a lesser extent, in the Hertzsprung-Russell diagram (HRD). The MRD ages of Mon-735 and CoRoT 223992193 are $\sim$7-9 and 4-6 Myr, respectively, with the two components in each EB system possessing consistent ages.

[5]  arXiv:2004.04754 [pdf, other]
Title: GASP XXV: Neutral Hydrogen gas in the striking Jellyfish Galaxy JO204
Comments: 16 pages, 10 figures, accepted for publication in MNRAS
Subjects: Astrophysics of Galaxies (astro-ph.GA)

We present JVLA-C observations of the HI gas in JO204, one of the most striking jellyfish galaxies from the GASP survey. JO204 is a massive galaxy in the low-mass cluster Abell 957 at z=0.04243. The HI map reveals an extended 90 kpc long ram-pressure stripped tail of neutral gas, stretching beyond the 30 kpc long ionized gas tail and pointing away from the cluster center. The HI mass seen in emission is (1.32 $ \pm 0.13) \times 10^{9} \rm M_{\odot}$, mostly located in the tail. The northern part of the galaxy disk has retained some HI gas, while the southern part has already been completely stripped and displaced into an extended unilateral tail. Comparing the distribution and kinematics of the neutral and ionized gas in the tail indicates a highly turbulent medium. Moreover, we observe associated HI absorption against the 11 mJy central radio continuum source with an estimated HI absorption column density of 3.2 $\times 10^{20}$ cm$^{-2}$. The absorption profile is significantly asymmetric with a wing towards higher velocities. We modelled the HI absorption by assuming that the HI and ionized gas disks have the same kinematics in front of the central continuum source, and deduced a wider absorption profile than observed. The observed asymmetric absorption profile can therefore be explained by a clumpy, rotating HI gas disk seen partially in front of the central continuum source, or by ram-pressure pushing the neutral gas towards the center of the continuum source, triggering the AGN activity.

[6]  arXiv:2004.04757 [pdf, other]
Title: Progenitor, Precursor and Evolution of the Dusty Remnant of the Stellar Merger M31-LRN-2015
Comments: 16 pages, 10 figures. Submitted to MNRAS
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)

M31-2015-LRN is a likely stellar merger discovered in the Andromeda Galaxy in 2015. We present new optical to mid-infrared photometry and optical spectroscopy for this event. The transient brightened by $\sim$3 mag as compared to its progenitor. The complex precursor emission, which started $\sim$2 years before the nova event, may be explained by the binary undergoing Roche-lobe overflow. The dynamical mass loss from the outer Lagrange point L2 creates an optically thick outflow to power the observed brightening of the system. We find two possible periods of 16$\pm$0.3 and 28.1$\pm$1.4 days at different phases of the precursor lightcurve, possibly related to the geometry of the mass-loss from the binary. Although the progenitor spectral energy distribution shows no evidence of pre-existing warm dust in system, the remnant forms an optically thick dust shell 2$-$4 months after the outburst peak. The optical depth of the shell increases after 1.5 years, suggesting the existence of shocks that enhance the dust formation process. We propose that the merger remnant is likely an inflated giant obscured by a cooling shell of gas with mass $\sim0.2$ $M_{\odot}$ ejected at the onset of the common envelope phase.

[7]  arXiv:2004.04762 [pdf, other]
Title: Direct Measurement of the HI-Halo Mass Relation through Stacking
Comments: 18 pages, 10 figures. Accepted for publication in ApJ
Subjects: Astrophysics of Galaxies (astro-ph.GA)

We present accurate measurements of the total HI mass in dark matter halos of different masses at z ~ 0, by stacking the HI spectra of entire groups from the Arecibo Fast Legacy ALFA Survey. The halos are selected from the optical galaxy group catalog constructed from the Sloan Digital Sky Survey DR7 Main Galaxy sample, with reliable measurements of halo mass and halo membership. We find that the HI-halo mass relation is not a simple monotonic function, as assumed in several theoretical models. In addition to the dependence of halo mass, the total HI gas mass shows strong dependence on the halo richness, with larger HI masses in groups with more members at fixed halo masses. Moreover, halos with at least three member galaxies in the group catalog have a sharp decrease of the HI mass, potentially caused by the virial halo shock-heating and the AGN feedback. The dominant contribution of the HI gas comes from the central galaxies for halos of $M<10^{12.5}h^{-1}M_{\odot}$, while the satellite galaxies dominate over more massive halos. Our measurements are consistent with a three-phase formation scenario of the HI-rich galaxies. The smooth cold gas accretion is driving the HI mass growth in halos of $M<10^{11.8}h^{-1}M_{\odot}$, with late-forming halos having more HI accreted. The virial halo shock-heating and AGN feedback will take effect to reduce the HI supply in halos of $10^{11.8}h^{-1}M_{\odot}<M<10^{13}h^{-1}M_{\odot}$. The HI mass in halos more massive than $10^{13}h^{-1}M_{\odot}$ generally grows by mergers, with the dependence on halo richness becoming much weaker.

[8]  arXiv:2004.04764 [pdf, other]
Title: The EXOTIME project: Signals in the $ O-C $ diagrams of the rapidly pulsating subdwarfs DW Lyn, V1636 Ori, QQ Vir, and V541 Hya
Comments: 22 pages, 23 figures, accepted for publication in A&A
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

We aim to investigate variations in the arrival time of coherent stellar pulsations due to the light-travel time effect to test for the presence of sub-stellar companions. Those companions are the key to one possible formation scenario of apparently single sub-dwarf B stars. We made use of an extensive set of ground-based observations of the four large amplitude p-mode pulsators DW Lyn, V1636 Ori, QQ Vir, and V541 Hya. Observations of the TESS space telescope are available on two of the targets. The timing method compares the phase of sinusoidal fits to the full multi-epoch light curves with phases from the fit of a number of subsets of the original time series. Observations of the TESS mission do not sample the pulsations well enough to be useful due to the (currently) fixed two-minute cadence. From the ground-based observations, we infer evolutionary parameters from the arrival times. The residual signals show many statistically significant periodic signals, but no clear evidence for changes in arrival time induced by sub-stellar companions. The signals can be explained partly by mode beating effects. We derive upper limits on companion masses set by the observational campaign.

[9]  arXiv:2004.04774 [pdf, other]
Title: Characterization of Optical Light Curves of Extreme Variability Quasars Over a ~16-yr Baseline
Subjects: Astrophysics of Galaxies (astro-ph.GA)

We study the optical light curves - primarily probing the variable emission from the accretion disk - of ~ 900 extreme variability quasars (EVQs, with maximum flux variations more than 1 mag) over an observed-frame baseline of ~ 16 years using public data from the SDSS Stripe 82, PanSTARRS-1 and the Dark Energy Survey. We classify the multi-year long-term light curves of EVQs into three categories roughly in the order of decreasing smoothness: monotonic decreasing or increasing (3.7%), single broad peak and dip (56.8%), and more complex patterns (39.5%). The rareness of monotonic cases suggests that the major mechanisms driving the extreme optical variability do not operate over timescales much longer than a few years. Simulated light curves with a damped random walk model generally under-predict the first two categories with smoother long-term trends. Despite the different long-term behaviors of these EVQs, there is little dependence of the long-term trend on the physical properties of quasars, such as their luminosity, BH mass, and Eddington ratio. The large dynamic range of optical flux variability over multi-year timescales of these EVQs allows us to explore the ensemble correlation between the short-term (< 6 months) variability and the seasonal-average flux across the decade-long baseline (the rms-mean flux relation). We find that unlike the results for X-ray variability studies, the linear short-term flux variations do not scale with the seasonal-average flux, indicating different mechanisms that drive the short-term flickering and long-term extreme variability of accretion disk emission. Finally, we present a sample of 16 EVQs, where the approximately bell-shaped large amplitude variation in the light curve can be reasonably well fit by a simple microlensing model.

[10]  arXiv:2004.04808 [pdf, other]
Title: Impact of dark matter models on the EoR 21-cm signal bispectrum
Comments: 12 pages, 11 figures, submitted in MNRAS. Comments are welcome
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)

The nature of dark matter sets the timeline for the formation of first collapsed halos and thus affects the sources of reionization. Here, we consider two different models of dark matter: cold dark matter (CDM) and thermal warm dark matter (WDM), and study how they impact the epoch of reionization (EoR) and its 21-cm observables. Using a suite of simulations, we find that in the WDM scenarios, the structure formation on small scales gets suppressed resulting in a smaller number of low mass dark matter halos compared to the CDM scenario. Assuming that the efficiency of sources in producing ionizing photons remain the same, this leads to a lower number of total ionizing photons produced at any given cosmic time and thus in a delay in the reionization process. We also find visual differences in the neutral hydrogen (HI) topology and in 21-cm maps in case of the WDM compared to the CDM. However, differences in the 21-cm power spectra, at the same neutral fraction, are found to be small. Thus, we focus on the non-Gaussianity in the EoR 21-cm signal, quantified through its bispectrum. We find that the 21-cm bispectra (driven by the HI topology) are significantly different in WDM models when compared with CDM, even for same mass averaged neutral fractions. This establishes that the 21-cm bispectrum is a unique and promising way to differentiate between different dark matter models, and can be used to constrain the nature of the dark matter in the future EoR observations.

[11]  arXiv:2004.04833 [pdf, other]
Title: 2D-FFTLog: Efficient computation of real space covariance matrices for galaxy clustering and weak lensing
Comments: 12 pages, 3 figures, 2 tables; 2DFFTLog code available at this https URL ; 3x2pt covariance code CosmoCov at this https URL
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA); Instrumentation and Methods for Astrophysics (astro-ph.IM)

Accurate covariance matrices for two-point functions are critical for inferring cosmological parameters in likelihood analyses of large-scale structure surveys. Among various approaches to obtaining the covariance, analytic computation is much faster and less noisy than estimation from data or simulations. However, the transform of covariances from Fourier space to real space involves integrals with two Bessel integrals, which are numerically slow and easily affected by numerical uncertainties. Inaccurate covariances may lead to significant errors in the inference of the cosmological parameters. In this paper, we introduce a 2D-FFTLog algorithm for efficient, accurate and numerically stable computation of non-Gaussian real space covariances. The 2D-FFTLog algorithm is easily extended to perform real space bin-averaging. We apply the algorithm to the covariances for galaxy clustering and weak lensing for a DES Y3-like and an LSST Y1-like survey, and demonstrate that for both surveys, our algorithm can produce numerically stable angular bin-averaged covariances at the flat sky limit, which are sufficiently accurate for inferring cosmological parameters.

[12]  arXiv:2004.04847 [pdf, other]
Title: CKS IX: Revisiting the Minimum-Mass Extrasolar Nebula with Precise Stellar Parameters
Comments: Accepted to AAS Journals
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)

We investigate a possible correlation between the solid surface density $\Sigma$ of the minimum-mass extrasolar nebulae (MMEN) and the host star mass $M_\star$ and metallicity [Fe/H]. Leveraging on the precise host star properties from the California-{\it Kepler}-Survey (CKS), we found that $\Sigma=$ 50^{+33}_{-20} \rm{~g~cm}^{-2} $(a/1AU)^{-1.75\pm0.07}$ $(M_\star/M_\odot)^{1.04\pm0.22}$ $10^{0.22\pm0.05{\rm [Fe/H]}}$ for {\it Kepler}-like systems (1-4$R_\oplus$; $a<$1AU). The strong $M_\star$ dependence is reminiscent of previous dust continuum results that the solid disk mass scales with $M_\star$. The weaker [Fe/H] dependence shows that sub-Neptune planets, unlike giant planets, form readily in lower-metallicity environment. The innermost region ($a<$ 0.1AU) of a MMEN maintains a smooth profile despite a steep decline of planet occurrence rate: a result that favors the truncation of disks by co-rotating magnetospheres with a range of rotation periods, rather than the sublimation of dusts. The $\Sigma$ of {\it Kepler} multi-transiting systems shows a much stronger correlation with $M_\star$ and [Fe/H] than singles. This suggests that the dynamically hot evolution that produced single systems also partially removed the memory of formation in disks. Radial-velocity planets yielded a MMEN very similar to CKS planets; transit-timing-variation planets' postulated convergent migration history is supported by their poorly constrained MMEN. We found that lower-mass stars have a higher efficiency of forming/retaining planets: for sun-like stars about 20\% of the solid mass within $\sim$1AU are converted/preserved as sub-Neptunes, compared to 70\% for late-K-early-M stars. This may be due to the lower binary fraction, lower giant-planet occurrence or the longer disk lifetime of lower-mass stars.

[13]  arXiv:2004.04886 [pdf, other]
Title: Edge collapse and subsequent longitudinal accretion in Filament S242
Comments: 14 pages, 11 figures; Accepted for publication in A&A
Subjects: Astrophysics of Galaxies (astro-ph.GA)

Filament S242 is 25 pc long with massive clumps and YSO clusters concentrated in its end regions; it is considered a good example of edge collapse. We mapped this filament in the $^{12}$CO(1-0) and $^{13}$CO(1-0) lines. A large-scale velocity gradient along filament S242 has been detected; the relative velocity between the two end-clumps is $\sim$ 3 km s$^{-1}$, indicating an approaching motion between them. These signatures are consistent with the filament S242 being formed through the collapse of a single elongated entity, where an effect known as "gravitational focusing" drives the ends of the filament to collapse (edge collapse). Based on this picture, we estimate a collapse timescale of $\sim$ 4.2 Myr, which is the time needed for a finite and elongated entity evolving to the observed filament S242. For the whole filament, we find that increases in surface densities lead to increases in velocity dispersion, which can be consistently explained as the result of self-gravity. We also calculated the contribution of longitudinal collapse to the observed velocity dispersion and found it to be the dominant effect in driving the gas motion near the end-clumps. We propose that our filament S242 is formed through a two-stage collapse model, where the edge collapse of a truncated filament is followed by a stage of longitudinal accretion toward the dense end-clumps.

[14]  arXiv:2004.04887 [pdf, ps, other]
Title: Searching for Molecular Outflows with Support Vector Machines: Dark Cloud Complex in Cygnus
Comments: 23 pages, 15 figures and 2 tables, accepted for publication in ApJS
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)

We present a survey of molecular outflows across the dark cloud complex in the Cygnus region, based on 46.75 deg^2 field of CO isotopologues data from Milky Way Imaging Scroll Painting (MWISP) survey. A supervised machine learning algorithm, Support Vector Machine (SVM), is introduced to accelerate our visual assessment of outflow features in the data cube of 12CO and 13CO J = 1-0 emission. A total of 130 outflow candidates are identified, of which 77 show bipolar structures and 118 are new detections. Spatially, these outflows are located inside dense molecular clouds and some of them are found in clusters or in elongated linear structures tracing the underlying gas filament morphology. Along the line of sight, 97, 31, and 2 candidates reside in the Local, Perseus, and Outer arm, respectively. Young stellar objects as outflow drivers are found near most outflows, while 36 candidates show no associated source. The clusters of outflows that we detect are inhomogeneous in their properties; nevertheless, we show that the outflows cannot inject turbulent energy on cloud scales. Instead, at best, they are restricted to affecting the so called "clump" and "core" scales, and this only on short (~0.3 Myr) estimated timescales. Combined with outflow samples in the literature, our work shows a tight outflow mass-size correlation.

[15]  arXiv:2004.04904 [pdf, other]
Title: An Extreme Ultraviolet Wave Associated with A Solar Filament Activation
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

Extreme ultraviolet (EUV) waves are impressive coronal propagating disturbances. They are closely associated with various eruptions, and can used for the global coronal seismology and the acceleration of solar energetic particles. Hence, the study of EUV waves plays an important role in solar eruptions and Space Weather. Here we present an EUV wave associated with a filament activation that did not evolve into any eruption. Due to the continuous magnetic flux emergence and cancellation around its one end, the filament rose with untwisting motion, and the filament mass flowed towards another end along the rising fields. Intriguingly, following the filament activation, an EUV wave formed with a fast constant speed ($\sim$500 km s$^{-1}$) ahead of the mass flow, and the overlying coronal loops expanded both in lateral and radial directions. Excluding the possibility of a remote flare and an absent coronal mass ejection, we suggest that the EUV wave was only closely associated with the filament activation. Furthermore, their intimate spacial and temporal relationship indicates that the EUV wave was likely directly triggered by the lateral expansion of overlying loops. We propose that the EUV wave can be interpreted as linear fast-mode wave, and the most vital key for the successful generation of the EUV wave is the impulsive early-phase lateral expansion of overlying loops that was driven by the activated filament mass flow without any eruption.

[16]  arXiv:2004.04930 [pdf]
Title: Study of Recent outburst in the Be/X-ray binary RX J0209.6-7427 with AstroSat: A new ultraluminous X-ray pulsar in the Magellanic Bridge?
Comments: 10 pages, 9 figures, accepted for publication in MNRAS Journal
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

We present the timing and spectral studies of RX J0209.6-7427 during its rare 2019 outburst using observations with the Soft X-ray Telescope (SXT) and Large Area X-ray Proportional Counter (LAXPC) instruments on the AstroSat satellite. Pulsations having a periodicity of 9.29 s were detected for the first time by the NICER mission in the 0.2-10 keV energy band and, as reported here, by AstroSat over a broad energy band covering 0.3-80 keV. The pulsar exhibits a rapid spin-up during the outburst. We also detect a glitch during the rapid spin-up of the pulsar. Energy resolved folded pulse profiles are generated in several energy bands in 3-80 keV. To the best of our knowledge this is the first report of the timing and spectral characteristics of this Be binary pulsar in hard X-rays. There is suggestion of evolution of the pulse profile with energy. An intriguing epoch of broadband decrease in the pulsed fraction is detected which suggests transition in the accretion regime of the pulsar. The energy spectrum of the pulsar is determined and from the best fit spectral values, the X-ray luminosity of RX J0209.6-7427 is inferred to be ${1.6}\times 10^{39}$ ergs s$^{-1}$. Our timing and spectral studies suggest that this source has features of an ultraluminous X-ray pulsar in the Magellanic Bridge. Details of the results are presented and discussed in terms of the current ideas.

[17]  arXiv:2004.04942 [pdf, other]
Title: Planet formation by pebble accretion in ringed disks
Comments: Accepted for publication in Astronomy & Astrophysics
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Context: Pebble accretion is expected to be the dominant process for the formation of massive solid planets, such as the cores of giant planets and super-Earths. So, far, this process has been studied under the assumption that dust coagulates and drifts throughout the full protoplanetary disk. However, observations show that many disks are structured in rings that may be due to pressure maxima, preventing the global radial drift of the dust.
Aims: We study how the pebble-accretion paradigm changes if the dust is confined in a ring.
Results: Planet Type-I migration is stopped in a ring, but not necessarily at its center. If the entropy-driven corotation torque is desaturated, the planet is located in a region with a low density of dust, which severely limits its accretion rate. If instead the planet is near the ring's center, its accretion rate can be similar to the one it would have in a classic (ring-less) disk of equivalent dust density. However, the growth rate of the planet is limited by the diffusion of dust in the ring and the final planet's mass is bounded by the total ring's mass. The DSHARP rings are too far from the star to allow the formation of massive planets within the disk's lifetime. However, a similar ring rescaled to 5 AU could lead to the formation of a planet incorporating the full ring's mass in less than 1/2 My.
Conclusions: The existence of rings may not be an obstacle to planet formation by pebble-accretion. However, for accretion to be effective the resting position of the planet has to be relatively near the ring's center and the ring needs to be not too far from the central star. The formation of planets in rings can explain the existence of giant planets with core masses smaller than the so-called pebble isolation mass.

[18]  arXiv:2004.04952 [pdf, other]
Title: Polarization measurements of the polluted white dwarf G29-38
Comments: 15 pages, 6 figures, 4 tables. Accepted to MNRAS
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)

We have made high precision polarimetric observations of the polluted white dwarf G29-38 with the HIgh Precision Polarimetric Instrument 2. The observations were made at two different observatories -- using the 8.1-m Gemini North Telescope and the 3.9-m Anglo AustralianTelescope -- and are consistent with each other. After allowing for a small amount of interstellar polarization, the intrinsic linear polarization of the system is found to be 275.3 +/- 31.9 parts-per-million at a position angle of 90.8 +/- 3.8 degrees in the SDSS g' band. We compare the observed polarization with the predictions of circumstellar disc models. The measured polarization is small in the context of the models we develop which only allows us to place limits on disc inclination and Bond albedo for optically thin disc geometries. In this case either the inclination is near face-on or the albedo is small -- likely in the range 0.05 to 0.15 -- which is in line with other debris disc measurements. A preliminary search for the effects of G29-38's pulsations in the polarization signal produced inconsistent results. This may be caused by beating effects, indicate a clumpy dust distribution, or be a consequence of measurement systematics.

[19]  arXiv:2004.04964 [pdf, other]
Title: Neutrino physics in slowly rotating black hole spacetime and nonlinear electrodynamics
Comments: 5 pages, 2 figures. Presented at NuPhys2019: Prospects in Neutrino Physics-Cavendish Conference Centre, London, 16-18 December 2019
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc)

Huge electromagnetic fields are known to be present during the late stages of the dynamics of supernovae. Thus, when dealing with electrodynamics in this context, the possibility may arise to probe nonlinear theories. The Einstein field equations minimally coupled to an arbitrary nonlinear Lagrangian of electrodynamics are solved in the regime of slow rotation, i.e. $a << M$ (black hole's mass), up to first order in $a/M$. We use Born-Infeld Lagrangian to compare the obtained results with Maxwellian counterpart. We focus on the astrophysics of neutrino flavor oscillations ($\nu_e\to\nu_{\mu, \tau}$) and spin-flip ($\nu_L\to\nu_R$), as well as on the computation of that the electron fraction $Y_e$, hence the r-processes, which may significantly differ with respect to the standard electrodynamics.

[20]  arXiv:2004.04991 [pdf, other]
Title: Liverpool-Maidanak monitoring of the Einstein Cross in 2006$-$2019. I. Light curves in the $gVrRI$ optical bands and microlensing signatures
Comments: Accepted to A&A; 10 pages, 10 long tables (Tables 4-8 and 10-14) are available at the CDS
Subjects: Astrophysics of Galaxies (astro-ph.GA)

Quasar microlensing offers a unique opportunity to resolve tiny sources in distant active galactic nuclei and study compact object populations in lensing galaxies. We therefore searched for microlensing-induced variability of the gravitationally lensed quasar QSO 2237+0305 (Einstein Cross) using 4374 optical frames taken with the 2.0 m Liverpool Telescope and the 1.5 m Maidanak Telescope. These $gVrRI$ frames over the 2006$-$2019 period were homogeneously processed to generate accurate long-term multi-band light curves of the four quasar images A-D. Through difference light curves, we found strong microlensing signatures. We then focused on the analytical modelling of two putative caustic-crossing events in image C, finding compelling evidence that this image experienced a double caustic crossing. Additionally, our overall results indicate that a standard accretion disc accounts reasonably well for the brightness profile of UV continuum emission sources and for the growth in source radius when the emission wavelength increases: $R_{\lambda} \propto \lambda^{\alpha}$, $\alpha$ = 1.33 $\pm$ 0.09. However, we caution that numerical microlensing simulations are required before firm conclusions can be reached on the UV emission scenario because the $VRI$-band monitoring during the first caustic crossing and one of our two $\alpha$ indicators lead to a few good solutions with $\alpha \approx$ 1.

[21]  arXiv:2004.04997 [pdf, other]
Title: Optical and infrared study of the obscured B[e] supergiant high-mass X-ray binary IGR J16318-4848
Comments: ApJ in press, 20 pages, 16 figures
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)

The supergiant High Mass X-ray Binary IGR J16318-4848 was the first source detected by the INTEGRAL satellite in 2003 and distinguishes itself by its high intrinsic absorption and B[e] phenomenon. It is the perfect candidate to study both binary interaction and the environment of supergiant B[e] stars. This study targets the local properties of IGR J16318-4848. We aim to clarify the geometry of this system, and distinguish different key emitting regions in the binary. We provide optical to near-infrared spectra from VLT/X-Shooter and analyse both fine structures of the lines and the broadband spectral energy distribution by adding archival mid-infrared Spitzer and Herschel data. We also performed a stellar atmosphere and wind modeling of the optical to near-infrared spectrum using the PoWR code. We determine the contribution of the irradiated inner edge of the dusty circumbinary disk, derive the velocity of an equatorial stellar wind, and suggest the compact object orbits within the cavity between the star and the disk. We report on flat-topped lines originating from a spherically symetric disk wind, along with the first detection of what is likely the polar component of the stellar wind. Stellar atmosphere and wind modeling shows that the central star may have a helium-enhanced atmosphere, likely because of its intense wind sheding part of its hydrogen envelope. Finally we compare the properties of IGR J16318-4848 with a similar source, CI Cameleopardis.

[22]  arXiv:2004.05000 [pdf, other]
Title: Cosmic spin and mass evolution of black holes and its impact
Authors: Dipanweeta Bhattacharyya, A. Mangalam (Indian Institute of Astrophysics)
Comments: 56 pages, 27 figures [74 sub-figures], 8 tables; accepted for publication in the Astrophysical Journal
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)

We build an evolution model of the central black hole that depends on the processes of gas accretion, the capture of stars, mergers as well as electromagnetic torque. In case of gas accretion in the presence of cooling sources, the flow is momentum-driven, after which the black hole reaches a saturated mass; subsequently, it grows only by stellar capture and mergers. We model the evolution of the mass and spin with the initial seed mass and spin in $\Lambda$CDM cosmology. For stellar capture, we have assumed a power-law density profile for the stellar cusp in a framework of relativistic loss cone theory that include the effects of black hole spin, Carter's constant, loss cone angular momentum, and capture radius. Based on this, the predicted capture rates of $10^{-5}$--$10^{-6}$ yr$^{-1}$ are closer to the observed range. We have considered the merger activity to be effective for $z \lesssim 4$, and we self-consistently include the Blandford-Znajek torque. We calculate these effects on the black hole growth individually and in combination, for deriving the evolution. Before saturation, accretion dominates the black hole growth ($\sim 95\%$ of the final mass), and subsequently, stellar capture and mergers take over with roughly equal contribution. The simulations of the evolution of the $M_{\bullet} - \sigma$ relation using these effects are consistent with available observations. We run our model backward in time and retrodict the parameters at formation. Our model will provide useful inputs for building demographics of the black holes and in formation scenarios involving stellar capture.

[23]  arXiv:2004.05016 [pdf, other]
Title: Can a conditioning on stellar mass explain the mutual information between morphology and environment?
Comments: 9 pages, 5 figures. Any comments and suggestions are welcome
Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)

Recent studies with SDSS have shown that a statistically significant non-zero mutual information between morphology and environment persists upto several tens of Mpc. It is important to understand the origin of these non-zero mutual information. Galaxies in different environments acquire their stellar mass through accretion and merger and the stellar mass function of galaxies is known to depend on both environment and morphology. Naturally, stellar mass can be an important link between morphology and environment which may explain the non-zero mutual information between the two. Measuring the mutual information between morphology and environment by conditioning the stellar mass would allow us to test this possibility. We compute the mutual information between morphology and environment by conditioning the stellar mass in a volume limited and stellar mass limited sample from SDSS DR16 and find a non-zero conditional mutual information throughout the entire length scales probed. The results suggest that only environmental and morphology dependence of stellar mass are inadequate in explaining the observed mutual information between morphology and environment. We compare the results with two semi analytic models implemented on the Millennium simulation. The predictions of the semi-analytic models are in fairly good agreement with the SDSS observations on smaller length scales but are noticeably smaller on larger length scales.

[24]  arXiv:2004.05019 [pdf, other]
Title: Revisiting the thermal relaxation of neutron stars
Comments: 9 pages, 15 figures
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

In this work we revisit the thermal relaxation process for neutron stars. Such process is associated with the thermal coupling between the core and the crust of neutron stars. The thermal relaxation, which takes place at around 10 -- 100 years, is manifested as a sudden drop of the star's surface temperature. Such drop is smooth for slow cooling objects and very sharp for those with fast cooling. In our study we focus particularly on the cooling of neutron stars whose mass is slightly greater than the value above which the direct Urca (DU) process sets in. Considering different mechanisms for neutrino production in each region of the star, and working with equations of state with different properties, we solve the thermal evolution equation and calculate the thermal relaxation time for ample range of neutron star masses. By performing a comprehensive study of neutron stars just above the onset of the direct Urca process we show that stars under these conditions exhibit a peculiar thermal relaxation behavior. We demonstrate that such stars exhibit an abnormally late relaxation time, characterized by a second drop of its surface temperature taking place a later ages. We qualify such behavior by showing that it is associated with limited spatial distribution of the DU process is such stars. We show that as the star's mass increase, the DU region also grows and the start exhibits the expected behavior of fast cooling stars. Finally we show that one can expect high relaxation times for stars in which the DU process takes place in a radius not larger than 3 km.

[25]  arXiv:2004.05049 [pdf, other]
Title: The $H_0$ tension: $ΔG_N$ vs. $ΔN_{\rm eff}$
Comments: 18 pages, 5 figures
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)

We investigate whether the $4.4\sigma$ tension on $H_0$ between SH$_{0}$ES 2019 and Planck 2018 can be alleviated by a variation of Newton's constant $G_N$ between the early and the late Universe. This changes the expansion rate before recombination, similarly to the addition of $\Delta N_{\rm eff}$ extra relativistic degrees of freedom . We implement a varying $G_N$ in a scalar-tensor theory of gravity, with a non-minimal coupling of the form $(M^2+\beta \phi^2)R$. If the scalar $\phi$ starts in the radiation era at an initial value $\phi_I \approx 0.3 \, M_{Pl}$ and with $\beta\approx-0.8$, a dynamical transition occurs naturally around the epoch of matter-radiation equality and the field evolves towards zero at late times. As a consequence the $H_0$ tension between SH$_{0}$ES (2019) and Planck 2018+BAO decreases, as in $\Delta N_{\rm eff}$ models. However, mostly due to late-time constraints from Post-Newtonian (PN) local gravity, the tension is reduced only to 3.5$\sigma$ level. When including also the SH$_{0}$ES data in the fit, the varying $G_N$ model has $H_0=69.2_{-0.75}^{+0.62}$ and an improvement of $\Delta\chi^2=-3.6$ compared to $\Lambda$CDM, at the cost of 2 extra parameters. This corresponds to a decrease of $7_{-6}^{+3}$ percent in the value of $G_N$ from the radiation era to the present time. For comparison, we update the fit of the $\Delta N_{\rm eff}$ model to the same dataset. We find that the $\Delta N_{\rm eff}$ model performs better than the simplest varying $G_N$ scenario, with $H_0=70_{-0.95}^{+0.93}$ and $\Delta\chi^2=-5.5$. The $\Lambda$CDM limit of the $\Delta N_{\rm eff}$ model is disfavored at slightly more than 2$\sigma$, since $\Delta N_{\rm eff}=0.316_{-0.15}^{+0.15}$.

[26]  arXiv:2004.05075 [pdf, ps, other]
Title: Spectral signatures of chromospheric condensation in a major solar flare
Comments: Accepted for publication by the Astrophysical Journal - 9th April 2020
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)

We study the evolution of chromospheric line and continuum emission during the impulsive phase of the X-class SOL2014-09-10T17:45 solar flare. We extend previous analyses of this flare to multiple chromospheric lines of Fe I, Fe II, Mg II, C I, and Si II, observed with IRIS, combined with radiative-hydrodynamical (RHD) modeling. For multiple flaring kernels, the lines all show a rapidly evolving double-component structure: an enhanced, emission component at rest, and a broad, highly red-shifted component of comparable intensity. The red-shifted components migrate from 25-50 km s$^{-1}$ towards the rest wavelength within $\sim$30 seconds.
Using Fermi hard X-ray observations, we derive the parameters of an accelerated electron beam impacting the dense chromosphere, using them to drive a RHD simulation with the RADYN code. As in Kowalski et al. 2017a, our simulations show that the most energetic electrons penetrate into the deep chromosphere, heating it to T$\sim$10,000 K, while the bulk of the electrons dissipate their energy higher, driving an explosive evaporation, and its counterpart condensation -- a very dense (n$_e \sim 2 \times 10^{14}$ cm$^{-3}$), thin layer (30--40 km thickness), heated to 8--12,000 K, moving towards the stationary chromosphere at up to 50 km s$^{-1}$.
The synthetic Fe II 2814.45A profiles closely resemble the observational data, including a continuum enhancement, and both a stationary and a highly red-shifted component, rapidly moving towards the rest wavelength. Importantly, the absolute continuum intensity, ratio of component intensities, relative time of appearance, and red-shift amplitude, are sensitive to the model input parameters, showing great potential as diagnostics.

[27]  arXiv:2004.05090 [pdf]
Title: Compositional distributions and evolutionary processes for the near-Earth object population: Results from the MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS
Journal-ref: Icarus, 324, 41-76, 2009
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

We report measured spectral properties for more than 1000 NEOs, representing>5% of the currently discovered population. Thermal flux detected below 2.5 {\mu}m allows us to make albedo estimates for nearly 50 objects, including two comets. Additional spectral data are reported for more than 350 Mars-crossing asteroids. Most of these measurements were achieved through a collaboration between researchers at the Massachusetts Institute of Technology and the University of Hawaii, with full cooperation of the NASA Infrared Telescope Facility (IRTF) on Mauna Kea. We call this project the MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS; myth-neos).

[28]  arXiv:2004.05135 [pdf, ps, other]
Title: The influence of small scale magnetic field on the heating of J0250+5854 polar cap
Comments: 9 pages, 10 figures
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)

The influence of surface small scale magnetic field on the heating of PSR J0250+5854 polar cap is considered. It is assumed that polar cap is heated only by reverse positrons, accelerated in pulsar diode. It is supposed that pulsar diode is in stationary state with lower plate nearby the star surface (polar cap model), occupies all pulsar tube crosssection and operates in regime of steady space charge limited electron flow. The influence of small scale magnetic field on electric field inside pulsar diode is taken into account. To calculate the electron-positron pairs production rate we take into account only the curvature radiation of primary electrons and its absorption in magnetic field. It is assumed that part of electro-positron pairs may be created in bound state (positronium). And later such positroniums are photoionized by thermal photons from star surface.

[29]  arXiv:2004.05149 [pdf, other]
Title: Quantifying the Effect of Power Spectral Density Uncertainty on Gravitational-Wave Parameter Estimation for Compact Binary Sources
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Instrumentation and Methods for Astrophysics (astro-ph.IM); General Relativity and Quantum Cosmology (gr-qc)

In order to perform Bayesian parameter estimation to infer the source properties of gravitational waves from compact binary coalescences (CBCs), the noise characteristics of the detector must be understood. It is typically assumed that the detector noise is stationary and Gaussian, characterized by a power spectral density (PSD) that is measured with infinite precision. We present a new method to incorporate the uncertainty in the power spectral density estimation into the Bayesian inference of the binary source parameters. We calculate the PSD for the first 11 gravitational-wave detections reported by LIGO and Virgo with an on-source method, using only data from the analysis segment to obtain posterior samples for the PSD, which is modeled analytically using the BayesLine algorithm [1] as a sum of a set of Lorentzians and a broadband spline. We demonstrate how to marginalize over the uncertainty encompassed in the full PSD posterior for these first 11 CBC detections and find that incorporating the PSD uncertainty only leads to variations in the positions and width of the binary parameter posteriors on the order of a few percent.

[30]  arXiv:2004.05158 [pdf, other]
Title: Twenty years of SpeX: Accuracy limits of spectral slope measurements in asteroid spectroscopy
Comments: 15 pages, 11 figures, accepted for publication in ApJS
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

We examined two decades of SpeX/NASA Infrared Telescope Facility observations from the Small Main-Belt Asteroid Spectroscopic Survey (SMASS) and the MIT-Hawaii Near-Earth Object Spectroscopic Survey (MITHNEOS) to investigate uncertainties and systematic errors in reflectance spectral slope measurements of asteroids. From 628 spectra of 11 solar analogs used for calibration of the asteroid spectra, we derived an uncertainty of 4.2%/micron on slope measurements over 0.8 to 2.4 micron. Air mass contributes to -0.92%/micron per 0.1 unit air mass difference between the asteroid and the solar analog, and therefore for an overall 2.8%/micron slope variability in SMASS and MITHNEOS designed to operate within 1.0 to 1.3 air mass. No additional observing conditions (including parallactic angle, seeing and humidity) were found to contribute systematically to slope change. We discuss implications for asteroid taxonomic classification works. Uncertainties provided in this study should be accounted for in future compositional investigation of small bodies to distinguish intrinsic heterogeneities from possible instrumental effects.

Cross-lists for Mon, 13 Apr 20

[31]  arXiv:2004.04304 (cross-list from hep-ph) [pdf, other]
Title: Cosmic-Ray Signatures of Dark Matter from a Flavor Dependent Gauge Symmetry Model with Neutrino Mass Mechanism
Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Astrophysical Phenomena (astro-ph.HE)

We propose an extension to the Standard Model accommodating two families of Dirac neutral fermions and Majorana fermions under additional ${U(1)_{e-\mu} \times Z_3\times Z_2}$ symmetries where ${U(1)_{e-\mu}}$ is a flavor dependent gauge symmetry related to the first and second family of the lepton sector, which features a two-loop induced neutrino mass model. The two families are favored by minimally reproducing the current neutrino oscillation data and two mass difference squares and canceling the gauge anomalies at the same time. As a result, we have a prediction for neutrino masses. The lightest Dirac neutral fermion is a dark matter candidate with tree-level interaction restricted to electron, muon and neutrinos, which makes it difficult to detect in direct dark matter search as well as indirect search focusing on the ${\tau}$-channel, such as through ${\gamma}$-rays. It may however be probed by search for dark matter signatures in electron and positron cosmic rays, and allows interpretation of a structure appearing in the CALET electron+positron spectrum around 350-400 GeV as its signature, with a boost factor $\approx$40 Breit-Wigner enhancement of the annihilation cross section.

[32]  arXiv:2004.04756 (cross-list from hep-ph) [pdf, other]
Title: Complete predictions for high-energy neutrino propagation in matter
Comments: 43 pages, 16 figures. NuPropEarth code available at this https URL
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)

We present complete predictions for the interactions of energetic neutrinos with matter as they propagate through Earth towards large-volume detectors. Our results are based on state-of-the-art calculations for the high-energy neutrino-matter interaction cross-sections, which we have implemented in the HEDIS module of GENIE. In addition to the dominant interaction process, deep inelastic scattering off quarks and gluons, we include the relevant subdominant channels: (in)elastic scattering off the photon field of nucleons, coherent scattering off the photon field of nuclei, as well as the scattering on atomic electrons via the Glashow resonance. Our predictions for the neutrino attenuation rates, based on this complete and reliable calculation, are provided by a new software package, NuPropEarth. We quantify the dependence of our results on the cross-section model, including nuclear corrections, the incidence angle, and the spectral index, and compare them with other publicly available tools. Our results provide an important contribution to the scientific harvest of ongoing and next-generation high-energy neutrino detection experiments.

[33]  arXiv:2004.04773 (cross-list from gr-qc) [pdf, ps, other]
Title: No static regular black holes in Einstein-complex-scalar-Gauss-Bonnet gravity
Comments: revtex4, no figures and tables
Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics of Galaxies (astro-ph.GA); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

In this brief report, we investigate the existence of 4-dimensional static spherically symmetric black holes (BHs) in the Einstein-complex-scalar-Gauss-Bonnet (EcsGB) gravity with an arbitrary potential $V(\phi)$ and a coupling $f(\phi)$ between the scalar field $\phi$ and the Gauss-Bonnet (GB) term. We find that static regular BH solutions with complex scalar hairs do not exist. This conclusion does not depend on the coupling between the GB term and the scalar field, nor on the scalar potential $V(\phi)$ and the presence of a cosmological constant $\Lambda$ (which can be either positive or negative), as longer as the scalar field remains complex and is regular across the horizon.

[34]  arXiv:2004.04922 (cross-list from physics.plasm-ph) [pdf, other]
Title: Ion versus electron heating in compressively driven astrophysical gyrokinetic turbulence
Subjects: Plasma Physics (physics.plasm-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Space Physics (physics.space-ph)

The partition of irreversible heating between ions and electrons in compressively driven (but subsonic) collisionless turbulence is investigated by means of nonlinear gyrokinetic simulations. We derive a prescription for the ion-to-electron heating ratio $Q_{\text{i}}/Q_{\text{e}}$ as a function of the compressive-to-Alfv\'enic driving power ratio $P_{\text{compr}}/P_{\text{AW}}$, of the ratio of ion thermal pressure to magnetic pressure $\beta_{\text{i}}$, and of the ratio of ion-to-electron background temperatures $T_{\text{i}}/T_{\text{e}}$. It is shown that $Q_{\text{i}}/Q_{\text{e}}$ is an increasing function of $P_{\text{compr}}/P_{\text{AW}}$. When the compressive driving is sufficiently large, $Q_{\text{i}}/Q_{\text{e}}$ approaches $\simeq P_{\text{compr}}/P_{\text{AW}}$. This indicates that, in turbulence with large compressive fluctuations, the partition of heating is decided at the injection scales, rather than at kinetic scales. Analysis of phase-space spectra shows that the energy transfer from inertial-range compressive fluctuations to sub-Larmor-scale kinetic Alfv\'en waves is absent for both low and high $\beta_{\text{i}}$, meaning that the compressive driving is directly connected to the ion entropy fluctuations, which are converted into ion thermal energy. This result suggests that preferential electron heating is a very special case requiring low $\beta_{\text{i}}$ and no, or weak, compressive driving. Our heating prescription has wide-ranging applications, including to the solar wind and to hot accretion disks such as M87 and Sgr A*.

[35]  arXiv:2004.05121 (cross-list from gr-qc) [pdf, other]
Title: Novel thick brane solutions with $U(1)$ symmetry breaking
Comments: 14 pages, 9 figures. Comments welcome
Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th)

In this work, using two scalar fields ($\phi$, $\psi$) coupled to 4+1 dimensional gravity, we construct novel topological brane solutions through an explicit $U(1)$ symmetry breaking term. The potential of this model is constructed so that two distinct degenerate vacua in the $\phi$ field exist, in analogy to the $\phi^{4}$ potential. Therefore, brane solutions appear due to the vacuum structure of the $\phi$ field. However, the topology and vacuum structure in the $\psi$ direction depends on the symmetry breaking parameter $\beta^{2}$, which leads to different types of branes. As a result, one can interpret the present model as a combination of a $\phi^{4}$ brane with an auxiliary field, which leads to deviations from the $\phi^{4}$ system with the brane achieving a richer internal structure. Furthermore, we analyse in detail the behaviour of the superpotentials, the warp factors, the Ricci and Kretschmann scalars and the Einstein tensor components. In addition to this, we explore the stability of the brane in terms of the free parameters of the model. The analysis presented here complements previous work and is sufficiently novel to be interesting.

Replacements for Mon, 13 Apr 20

[36]  arXiv:1906.01674 (replaced) [pdf, ps, other]
Title: Neutron matter at the interface(s): static response and effective mass
Comments: 12 pages, 8 figures; v2 corresponds to published version
Journal-ref: Eur. Phys. J. A 56, 112 (2020)
Subjects: Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); Quantum Gases (cond-mat.quant-gas)
[37]  arXiv:1906.06641 (replaced) [pdf, other]
Title: Fitting formulae for evolution tracks of massive stars under extreme metal poor environments for population synthesis calculations and star cluster simulations
Comments: 22 pages, 15 figures, 8 tables
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR)
[38]  arXiv:1906.07119 (replaced) [pdf, other]
Title: AMS-02 antiprotons' consistency with a secondary astrophysical origin
Comments: 16 pages, 12 figures, published in PRR, title and few sentences changed (after 8 months of review)
Journal-ref: Phys. Rev. Research 2, 023022 (2020)
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Phenomenology (hep-ph)
[39]  arXiv:1907.03778 (replaced) [pdf, other]
Title: A local resolution of the Hubble tension: The impact of screened fifth forces on the cosmic distance ladder
Comments: 20 pages, 7 figures; correction to Eq 16, H0 results weakened slightly
Journal-ref: Phys. Rev. D 100, 043537 (2019)
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); Astrophysics of Galaxies (astro-ph.GA)
[40]  arXiv:1910.02504 (replaced) [pdf, other]
Title: Detecting Magnetic Fields in Exoplanets with Spectropolarimetry of the Helium Line at 1083 nm
Comments: published in The Astrophysical Journal on February 14, 2020; updated to match the published version
Journal-ref: ApJ 890, 88 (2020)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
[41]  arXiv:1910.07868 (replaced) [pdf, other]
Title: Large-scale structures in the $Λ$CDM Universe: network analysis and machine learning
Comments: 10 pages, 12 figures, accepted for publication in MNRAS
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
[42]  arXiv:1911.02179 (replaced) [pdf, other]
Title: Weak cosmic growth in coupled dark energy with a Lagrangian formulation
Comments: 15 pages, 2 figures, published version
Journal-ref: Phys. Lett. B 804, 135400 (2020)
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)
[43]  arXiv:1911.05756 (replaced) [pdf, other]
Title: Can astrophysical neutrinos trace the origin of the detected ultra-high energy cosmic rays?
Comments: 11 pages, 7 figures, accepted for publication in MNRAS; Updated to match version to appear in MNRAS
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
[44]  arXiv:1911.07886 (replaced) [pdf, ps, other]
Title: Fitting the nonlinear matter bispectrum by the Halofit approach
Comments: 23 pages, 15 figures, submitted to ApJ; revised version; numerical codes of the fitting formula are available at this https URL (Python) and this http URL (C and Fortran)
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
[45]  arXiv:1912.00242 (replaced) [pdf, other]
Title: $H_0$ tension and the String Swampland
Comments: v2: Extended discussion on the combined effect of fading dark matter and N_eff; references added
Subjects: High Energy Physics - Theory (hep-th); Cosmology and Nongalactic Astrophysics (astro-ph.CO); High Energy Physics - Phenomenology (hep-ph)
[46]  arXiv:1912.02086 (replaced) [pdf, other]
Title: Constraining the Milky Way Mass Profile with Phase-Space Distribution of Satellite Galaxies
Comments: Accepted for publication in ApJ; data tables available at this https URL
Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
[47]  arXiv:1912.02689 (replaced) [pdf, other]
Title: Gravity-mediated Dark Matter in Clockwork/Linear Dilaton Extra-Dimensions
Comments: 26 pages, 6 figures. Published version. arXiv admin note: text overlap with arXiv:1907.04340
Journal-ref: J. High Energ. Phys. 2020, 36 (2020)
Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE)
[48]  arXiv:1912.09826 (replaced) [pdf, other]
Title: Properties of OB star-black hole systems derived from detailed binary evolution models
Comments: 19 pages, 14 figures, Astronomy and Astrophysics, in press
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); High Energy Astrophysical Phenomena (astro-ph.HE)
[49]  arXiv:2001.00133 (replaced) [pdf, other]
Title: Clumpy AGN outflows due to thermal instability
Comments: 8 pages, 4 figures, 1 table, movies and additional information available on our project webpage: this http URL
Subjects: Astrophysics of Galaxies (astro-ph.GA)
[50]  arXiv:2001.02651 (replaced) [pdf, ps, other]
Title: The mass of our Galaxy from satellite proper motions in the Gaia era
Comments: 17 pages, 10 figures, 2 tables. Accepted for publication in MNRAS
Subjects: Astrophysics of Galaxies (astro-ph.GA)
[51]  arXiv:2001.02897 (replaced) [pdf, ps, other]
Title: Second law of black hole thermodynamics
Authors: Koji Azuma, Go Kato
Comments: 7 pages, 1 figure
Subjects: High Energy Physics - Theory (hep-th); High Energy Astrophysical Phenomena (astro-ph.HE); Statistical Mechanics (cond-mat.stat-mech); General Relativity and Quantum Cosmology (gr-qc); Quantum Physics (quant-ph)
[52]  arXiv:2002.06550 (replaced) [pdf, other]
Title: Oscillations of the baseline of solar magnetic field and solar irradiance on a millennial timescale
Comments: 7 pages, 5 figures
Subjects: Solar and Stellar Astrophysics (astro-ph.SR); Earth and Planetary Astrophysics (astro-ph.EP)
[53]  arXiv:2002.10265 (replaced) [pdf, ps, other]
Title: Periodicity in fast radio bursts due to forced precession by a fallback disk
Comments: 7 pages, accepted in RAA
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
[54]  arXiv:2003.03283 (replaced) [pdf, other]
Title: Performance and energy footprint assessment of FPGAs and GPUs on HPC systems using Astrophysics application
Comments: 15 pages, 4 figures, 3 tables; Preprint (V2) submitted to MDPI (Special Issue: Energy-Efficient Computing on Parallel Architectures)
Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Performance (cs.PF)
[55]  arXiv:2003.08416 (replaced) [pdf, ps, other]
Title: Chiral Symmetry and the Cosmological Constant
Comments: 10 pages, reformatted, some typographical errors corrected, results unchanged
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)
[56]  arXiv:2003.10095 (replaced) [pdf, other]
Title: Can $f(T)$ gravity resolve the $H_0$ tension?
Authors: Deng Wang, David Mota
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
[57]  arXiv:2003.10641 (replaced) [pdf, other]
Title: The effect of surface gravity on line-depth ratios in the wavelength range 0.97-1.32 μm
Comments: 12 pages, 7 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)
[58]  arXiv:2003.12057 (replaced) [pdf, other]
Title: Resolving Hubble Tension by Self-Interacting Neutrinos with Dirac Seesaw
Comments: 24 pages, only minor refinements, references added
Subjects: High Energy Physics - Phenomenology (hep-ph); Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
[59]  arXiv:2003.12722 (replaced) [pdf, other]
Title: Power and spatial complexity in stochastic reconnection
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); Plasma Physics (physics.plasm-ph)
[60]  arXiv:2003.14248 (replaced) [pdf, other]
Title: Liquid argon scintillation response to electronic recoils between $2.8$--$1275~{\rm keV}$ in a high light yield single-phase detector
Comments: 10 pages, 13 figures, 2 tables
Subjects: Instrumentation and Detectors (physics.ins-det); Instrumentation and Methods for Astrophysics (astro-ph.IM)
[61]  arXiv:2004.00018 (replaced) [pdf, other]
Title: Purveyors of fine halos. II. Chemodynamical association of halo stars with Milky Way globular clusters
Comments: 20 pages (+9 pages of appendices), 39 figures, 4 tables, accepted for publication in A&A
Subjects: Astrophysics of Galaxies (astro-ph.GA)
[62]  arXiv:2004.04337 (replaced) [pdf, ps, other]
Title: GeV emission of gamma-ray binary with pulsar scenario
Comments: 13 pages, 18 figures, 2 tables, accepted for publication in MNRAS
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE)
[63]  arXiv:2004.04360 (replaced) [pdf, other]
Title: The Lyman Continuum Escape Fraction of Galaxies and AGN in the GOODS Fields
Authors: Brent M. Smith (1), Rogier A. Windhorst (1), Seth H. Cohen (1), Anton M. Koekemoer (2), Rolf A. Jansen (1), Cameron White (3), Sanchayeeta Borthakur (1), Nimish Hathi (2), Linhua Jiang (4), Michael Rutkowski (5), Russell E. Ryan Jr. (2), Akio K. Inoue (6 and 7), Robert W. O'Connell (8), John W. MacKenty (2), Christopher J. Conselice (9), Joseph I. Silk (10) ((1) ASU/SESE, Tempe, AZ, USA, (2) STScI, Baltimore, MD, USA, (3) UA, Tucson, AZ, USA, (4) PKU/Kavli, Beijing, China, (5) MSU Mankato, Mankato, MN, USA, (6) Waseda U., Tokyo, Japan, (7) Waseda RISE, Tokyo, Japan, (8) UVa, Charlottesville, VA, USA, (9) UNott, Nottingham, UK, (10) JHU, Baltimore, MD, USA)
Comments: 36 pages, 17 figures, 5 tables. Accepted for publication in The Astrophysical Journal. v1 abstract latex errors corrected, minor changes to table 5, orcid ID corrected for one author
Subjects: Astrophysics of Galaxies (astro-ph.GA); Cosmology and Nongalactic Astrophysics (astro-ph.CO)
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