Sazuna/UAT_keywords huggingface dataset:
The Cosmic History of Long Gamma-Ray Bursts. The cosmic formation rate of long gamma-ray bursts (LGRBs) encodes the evolution, across cosmic times, of the properties of their progenitors and of their environment. The LGRB formation rate and the luminosity function, with its redshift evolution, are derived by reproducing the largest sets of observations collected over the last four decades, namely the observer-frame prompt emission properties of the GRB samples detected by the Fermi and Compton Gamma Ray Observatory satellites and the redshift, luminosity, and energy distributions of the flux-limited, redshift-complete samples of GRBs detected by Swift. The model that best reproduces all these constraints consists of a GRB formation rate increasing with redshift ∝(1 + z)3.2, i.e., steeper than the star formation rate, up to z ~ 3, followed by a decrease ∝(1 + z)-3. On top of this, our model also predicts a moderate evolution of the characteristic luminosity function break ∝(1 + z)0.6. Models with only luminosity or rate evolution are excluded at &gt;5σ significance. The cosmic rate evolution of LGRBs is interpreted as their preference for occurring in environments with metallicity $12+\mathrm{log}({\rm{O}}/{\rm{H}})\lt 8.6$ , consistent with theoretical models and host galaxy observations. The LGRB rate at z = 0, accounting for their collimation, is ${\rho }_{0}\,=\,{79}_{-33}^{+57}$ Gpc-3 yr-1 (68% confidence interval). This corresponds to ~1% of broad-line Type Ibc supernovae producing a successful jet in the local universe. This fraction increases up to ~7% at z ≥ 3. Finally, we estimate that at least ≈0.2-0.7 yr-1 of the Swift- and Fermi-detected bursts at z &lt; 0.5 are jets observed slightly off-axis.

Keywords: Gamma-ray bursts, Star formation
Invariable X-Ray Profile and Flux of the Crab Pulsar during Its Two Glitches. We compare the X-ray profiles and fluxes of the Crab pulsar before and after the glitches in 2017 and 2019, using the data collected by the Insight-HXMT, NICER, and Fermi/GBM, to test whether there is any evidence for magnetosphere rearrangement after glitch. For the 2017 glitch, the profiles from Insight-HXMT (27-200 keV) and NICER (0.5-10 keV) remain unchanged within rms 0.47% and 0.28%, respectively, while the pulsed fluxes measured by these two detectors remain stable with 1σ uncertainty of 0.07% and 0.011%. Considering that the persistent offset of the spin-down rate post-glitch is 0.13% and the X-ray luminosity of the Crab pulsar is proportional to ${\dot{E}}^{1.6\pm 0.3}$ , we find that the X-ray flux does not increase proportionally to the spin-down power at a significance of about 2.8σ by fitting the flux measurements with a Heaviside function, and thus the additional torque constantly braking the pulsar spin post-glitch is unlikely due to a global magnetosphere variation. For the 2019 glitch, after which a possible soft X-ray polarization variation was detected, the profiles remain unchanged within rms 2.02%, 0.35%, 0.90%, and 0.47% in 10-200, 0.5-10, 3-4.5, and 27-200 keV, respectively, suggesting that the geometry of the X-ray emitting region after the glitch is similar to the pre-glitch one. Therefore the possible polarization variation during the 2019 glitch is unlikely a consequence of the overall magnetosphere changes. The invariance of the pulse profiles is also verified by Kolmogorov-Smirnov tests and that of pulsed fluxes by Z-tests.

Keywords: Rotation powered pulsars
Radio Spectral Energy Distributions for Single Massive Star Winds with Free-Free and Synchrotron Emission. The mass-loss rates from single massive stars are high enough to form radio photospheres at large distances from the stellar surface, where the wind is optically thick to (thermal) free-free opacity. Here we calculate the far-infrared, millimeter, and radio band spectral energy distributions (SEDs) that can result from the combination of free-free processes and synchrotron emission, to explore the conditions for nonthermal SEDs. Simplifying assumptions are adopted in terms of scaling relations for the magnetic field strength and the spatial distribution of relativistic electrons. The wind is assumed to be spherically symmetric, and we consider the effect of Razin suppression on the synchrotron emission. Under these conditions, long-wavelength SEDs with synchrotron emission can be either more steep or more shallow than the canonical asymptotic power-law SED from a nonmagnetic wind. When nonthermal emission is present, the resultant SED shape is generally not a power law; however, the variation in the slope can change slowly with wavelength. Consequently, over a limited range of wavelengths, the SED can masquerade as approximately a power law. While most observed nonthermal long-wavelength spectra are associated with binarity, synchrotron emission can have only a mild influence on single-star SEDs, requiring finer levels of wavelength sampling for the detection of the effect.

Keywords: Early-type stars, Stellar magnetic fields, Stellar mass loss, Stellar winds, Non-thermal radiation sources, Radio continuum emission
Interpreting the Statistical Properties of High-z Extragalactic Sources Detected by the South Pole Telescope Survey. The results of the recently published spectroscopically complete survey of dusty star-forming galaxies detected by the South Pole Telescope over 2500 deg2 proved to be challenging for galaxy formation models that generally underpredict the observed abundance of high-z galaxies. In this paper we interpret these results in the light of a physically grounded model for the evolution of spheroidal galaxies. The model accurately reproduces the measured redshift distribution of galaxies without any adjustment of the parameters. The data do not support the indications of an excess of z &gt; 4 dusty galaxies reported by some analyses of Herschel surveys.

Keywords: High-redshift galaxies
Two Massive Close Binaries with Twin Components in the Nearby Galaxy M31. Massive contact binaries contain two early-type stars that have filled their respective critical Roche lobes and share a common envelope. Their formation and evolution are still unknown. Searching for massive binaries in special evolutionary stages is required to solve this problem. Many massive binaries in the Andromeda galaxy (M31) have been found out and they provide an ideal laboratory to explore the formation of massive contact binaries and to test evolutionary models in massive binaries. By analyzing the light curves of two massive binaries containing twin components, M31V J00452011+4145037 (hereafter J004520) and M31V J00450522+4138462 (hereafter J004505), observed by Vilardell et al., we found that J004520 is a semidetached binary with a mass ratio of 0.924 and a lobe-filling secondary, while J004505 is a deep-contact binary with a mass ratio of 0.974 and a fill-out factor of 88%. Both of them evolved from originally detached binaries via case A mass transfer and are at a critical evolutionary state with the shortest possible period and the highest possible mass ratio (q = 1). The evolution of J004520 has passed the critical state and cannot evolve into a contact binary, while J004505 is just close to the key state. The asymmetric light curve of J004505 is explained by the presence of a hot spot on the less-massive component caused by mass transfer from the more-massive one; the same conclusion can be obtained from the O - C curve. These results support the conclusion that massive contact binaries are formed from mass transfer between the two components and only some systems can evolve into the contact stage.

Keywords: Eclipsing binary stars, Andromeda Galaxy, Early stellar evolution, Contact binary stars
Comparing Tip of the Red Giant Branch Distance Scales: An Independent Reduction of the Carnegie-Chicago Hubble Program and the Value of the Hubble Constant. The tip of the red giant branch has been used to measure distances to 500 nearby galaxies with the Hubble Space Telescope (HST) which are available in the Color-Magnitude Diagrams and Tip of the Red Giant Branch (CMDs/TRGB) catalog on the Extragalactic Distance Database (EDD). Our established methods are employed to perform an independent reduction of the targets presented by the Carnegie-Chicago Hubble Program (CCHP) in the series of papers culminating in Freedman (2021). Our distinct methodology involves modeling the observed luminosity function of red giant branch and asymptotic giant branch stars, which differs from the edge-detection algorithms employed by the CCHP. We find excellent agreement between distances for 11 hosts with new imaging, all at D &lt; 20 Mpc. However, we are unable to measure the TRGB for four hosts that use archival data designed to measure distances with Cepheids, all at D &gt; 23 Mpc. With two new HST observations taken in the halo of the megamaser host NGC 4258, the first with the same ACS F606W and F814W filters and state of the electronics used for SN Ia hosts, we then calibrate our TRGB distance scale to the geometric megamaser distance. Using our TRGB distances, we find a value of the Hubble Constant of H 0 = 71.5 ± 1.8 km s-1 Mpc-1 when using either the Pantheon or Carnegie Supernova Project (CSP) samples of supernovae. In the future, the James Webb Space Telescope will extend measurements of the TRGB to additional hosts of SN Ia and surface-brightness fluctuation measurements for separate paths to H 0.

Keywords: Stellar populations, Red giant tip, Hubble constant, Distance indicators
An Arbitrarily High-order Spectral Difference Method with Divergence Cleaning (SDDC) for Compressible Magnetohydrodynamic Simulations on Unstructured Grids. This paper reports a recent development of the high-order spectral difference method with divergence cleaning (SDDC) for accurate simulations of both ideal and resistive magnetohydrodynamics (MHD) on curved unstructured grids consisting of high-order isoparametric quadrilateral elements. The divergence cleaning approach is based on the improved generalized Lagrange multiplier, which is thermodynamically consistent. The SDDC method can achieve an arbitrarily high order of accuracy in spatial discretization, as demonstrated in the test problems with smooth solutions. The high-order SDDC method combined with the artificial dissipation method can sharply capture shock interfaces with the oscillation-free property and resolve small-scale vortex structures and density fluctuations on relatively sparse grids. The robustness of the codes is demonstrated through long time simulations of ideal MHD problems with progressively interacting shock structures, resistive MHD problems with high Lundquist numbers, and viscous resistive MHD problems on complex curved domains.

Keywords: Hydrodynamical simulations, Magnetohydrodynamics, Distributed computing, Plasma astrophysics, Computational methods, Shocks, Magnetic fields, Magnetohydrodynamical simulations
Imaging of the Quiet Sun in the Frequency Range of 20-80 MHz. Radio emission of the quiet Sun is considered to be due to thermal bremsstrahlung emission of the hot solar atmosphere. The properties of the quiet Sun in the microwave band have been well studied, and they can be well described by the spectrum of bremsstrahlung emission. In the meter-wave and decameter-wave bands, properties of the quiet Sun have rarely been studied due to the instrumental limitations. In this work, we use the LOw Frequency ARray telescope to perform high quality interferometric imaging spectroscopy observations of quiet Sun coronal emission at frequencies below 90 MHz. We present the brightness temperature spectrum and the size of the Sun in the frequency range of 20-80 MHz. We report on dark coronal regions with low brightness temperatures that persist with frequency. The brightness temperature spectrum of the quiet Sun is discussed and compared with the bremsstrahlung emission of a coronal model and previous quiet Sun observations.

Keywords: Radio interferometry, Quiet sun, Solar radio emission
Atmospheric Circulation in Simulations of the AGN-CGM Connection at Halo Masses 10<SUP>13.5</SUP> M <SUB>⊙</SUB>. Coupling between active galactic nuclei (AGNs) and the circumgalactic medium (CGM) is critical to the interplay between radiative cooling and feedback heating in the atmospheres of the universe's most massive galaxies. This paper presents a detailed analysis of numerical simulations showing how kinetic AGN feedback with a strong momentum flux interacts with the CGM. Our analysis shows that large-scale CGM circulation driven by that momentum flux plays an important role in reconfiguring the galactic atmosphere and regulating the atmosphere's central entropy level. We find that most of the AGN's energy output goes into lifting of circumgalactic gas rather than heating of atmospheric gas within the galaxy, consequently reconfiguring the CGM by replacing low-entropy gas originally in the core with higher-entropy gas from larger radii. Circulation of the CGM on ~10-100 kpc scales therefore plays a critical role in preventing overcooling of gas in these simulated galaxies, but leads to elevated entropy profiles ~1-10 kpc compared to the observed entropy profiles of massive elliptical galaxies in the same mass range. The simulations also show that our choices of accretion efficiency and jet opening angle significantly affect the AGN-CGM coupling. Reducing the jet opening angle to one-quarter of the fiducial opening angle increases the jet momentum flux, enabling it to drill through to larger radii without effectively coupling with the CGM at the center (r &lt; 5 kpc). Outflows with a lower momentum flux decelerate and thermalize the bulk of their energy at smaller radii (r ≲ 10 kpc).

Keywords: Supermassive black holes, Stellar feedback, Active galaxies, Radio galaxies, Active galactic nuclei, Galaxy groups, Circumgalactic medium
RR Lyrae-based Distances for 39 Nearby Dwarf Galaxies Calibrated to Gaia eDR3. We provide uniform RR Lyrae-based distances to 39 dwarf galaxies in and around the Local Group. We determine distances based on a Bayesian hierarchical model that uses periods and magnitudes of published RR Lyrae in dwarf galaxies and is anchored to well-studied Milky Way (MW) RR Lyrae with spectroscopic metallicities and Gaia eDR3 parallaxes. Gaia eDR3 parallaxes for the anchor sample are a factor of 2, on average, more precise than DR2 parallaxes, and allow for a much better constrained period-luminosity-metallicity relation. While ~75% of our distances are within 1σ of recent RR Lyrae distances in the literature, our distances are also ~2-3 times more precise than distances in the literature, on average. On average, our distances are ~0.05 mag closer than distances in the literature, as well as ~0.06 mag closer than distances derived using a theoretical period-luminosity-metallicity relation. These discrepancies are largely due to our eDR3 parallax anchor. We show that the Hipparcos-anchored RR Lyrae distance scale of Carretta et al. overpredicts distances to MW RR Lyrae by ~0.05 mag. The largest uncertainties in our distances are (i) the lack of direct metallicity measurements for RR Lyrae and (ii) the heterogeneity of published RR Lyrae photometry. We provide simple formulae to place new dwarf galaxies with RR Lyrae on a common distance scale with this work. We provide a public code that can easily incorporate additional galaxies and data from future surveys, providing a versatile framework for the cartography of the local universe with RR Lyrae.

Keywords: Local Group, RR Lyrae variable stars, Galaxy distances, Dwarf galaxies
Linking Atmospheric Chemistry of the Hot Jupiter HD 209458b to Its Formation Location through Infrared Transmission and Emission Spectra. The elemental ratios of carbon, nitrogen, and oxygen in the atmospheres of hot Jupiters may hold clues to their formation locations in the protostellar disk. In this work, we adopt gas-phase chemical abundances of C, N, and O from several locations in a disk chemical kinetics model as sources for the envelope of the hot Jupiter HD 209458b and evolve the atmospheric composition of the planet using a 1D chemical kinetics model, treating both vertical mixing and photochemistry. We consider two atmospheric pressure-temperature profiles, one with and one without a thermal inversion. From each of the resulting 32 atmospheric composition profiles, we find that the molecules CH4, NH3, HCN, and C2H2 are more prominent in the atmospheres computed using a realistic noninverted P-T profile in comparison to a prior equilibrium chemistry based work, which used an analytical P-T profile. We also compute the synthetic transmission and emission spectra for these atmospheres and find that many spectral features vary with the location in the disk where the planetary envelope was accreted. By comparing with the species detected using the latest high-resolution ground-based observations, our model suggests that HD 209458b could have accreted most of its gas between the CO2 and CH4 ice lines with a supersolar C/O ratio from its protostellar disk, which in turn directly inherited its chemical abundances from the protostellar cloud. Finally, we simulate observing the planet with the James Webb Space Telescope (JWST) and show that differences in spectral signatures of key species can be recognized. Our study demonstrates the enormous importance of JWST in providing new insights into hot-Jupiter formation environments.

Keywords: Protoplanetary disks, Exoplanet atmospheres
Radio Emission from Binary Ultracool Dwarf Systems. Well-characterized binary systems will provide valuable opportunities to study the conditions that are necessary for the onset of both auroral and nonauroral magnetospheric radio emission in the ultracool dwarf regime. We present new detections of nonauroral "quiescent" radio emission at 4-8 GHz of the three ultracool dwarf binary systems GJ 564 BC, LP 415-20, and 2MASS J21402931+1625183. We also tentatively detect a highly circularly polarized pulse at 4-6 GHz that may indicate aurorae from GJ 564 BC. Finally, we show that the brightest binary ultracool dwarf systems may be more luminous than predictions from single-object systems.

Keywords: Radio continuum emission, Brown dwarfs, Binary stars, Magnetic fields
A Spectroscopic Survey of Infrared 1-4 μm Spectra in Regions of Prominent Solar Coronal Emission Lines of Fe XIII, Si X, and Si IX. The infrared solar spectrum contains a wealth of physical data about the Sun and is being explored using modern detectors and technology with new ground-based solar telescopes. One such instrument will be the ground-based Cryogenic Near-IR Spectro-Polarimeter of the Daniel K. Inouye Solar Telescope (DKIST), which will be capable of sensitive imaging of the faint infrared solar coronal spectra with full Stokes I, Q, U, and V polarization states. Highly ionized magnetic dipole emission lines have been observed in galaxies and the solar corona. Quantifying the accuracy of spectral inversion procedures requires a precise spectroscopic calibration of observations. A careful interpretation of the spectra around prominent magnetic dipole lines is essential for deriving physical parameters and particularly for quantifying the off-limb solar coronal observations from DKIST. In this work, we aim to provide an analysis of the spectral regions around the infrared coronal emission lines of Fe XIII 1074.68 nm, Fe XIII 1079.79 nm, Si X 1430.10 nm, and Si IX 3934.34 nm, aligning with the goal of identifying solar photospheric and telluric lines that will help facilitate production of reliable inversions and data products from four sets of solar coronal observations. The outputs can be integrated in processing pipelines to produce level 2 science-ready data.

Keywords: Astronomy data analysis, Solar coronal lines, Solar corona, Spectroscopy, Galaxy spectroscopy
A Multiwavelength Study of the Highly Asymmetrical Debris Disk around HD 111520. We observed the nearly edge-on debris disk system HD 111520 at the HJ and K1 near-infrared (NIR) bands using both the spectral and polarization modes of the Gemini Planet Imager. With these new observations, we have performed an empirical analysis in order to better understand the disk morphology and its highly asymmetrical nature. We find that the disk features a large brightness and radial asymmetry, most prominent at shorter wavelengths. We also find that the radial location of the peak polarized intensity differs on either side of the star by 11 au, suggesting that the disk may be eccentric, although, such an eccentricity does not fully explain the large brightness and radial asymmetry observed. Observations of the disk halo with the Hubble Space Telescope also show the disk to be warped at larger separations, with a bifurcation feature in the northwest, further suggesting that there may be a planet in this system creating an asymmetrical disk structure. Measuring the disk color shows that the brighter extension is bluer compared to the dimmer extension, suggesting that the two sides have different dust grain properties. This finding, along with the large brightness asymmetry, are consistent with the hypothesis that a giant impact occurred between two large bodies in the northern extension of the disk, although confirming this based on NIR observations alone is not feasible. Follow-up imaging with the Atacama Large Millimeter/submillimeter Array to resolve the asymmetry in the dust mass distribution is essential in order to confirm this scenario.

Keywords: Near infrared astronomy, Debris disks, Polarimetry, Circumstellar disks
How Binaries Accrete: Hydrodynamic Simulations with Passive Tracer Particles. Linear analysis of gas flows around orbiting binaries suggests that a centrifugal barrier ought to clear a low-density cavity around the binary and inhibit mass transfer onto it. Modern hydrodynamics simulations have confirmed the low-density cavity, but show that any mass flowing from large scales into the circumbinary disk is eventually transferred onto the binary components. Even though many numerical studies confirm this picture, it is still not understood precisely how gas parcels overcome the centrifugal barrier and ultimately accrete. We present a detailed analysis of the binary accretion process, using an accurate prescription for evolving grid-based hydrodynamics with Lagrangian tracer particles that track the trajectories of individual gas parcels. We find that binary accretion can be described in four phases: (1) gas is viscously transported through the circumbinary disk up to the centrifugal barrier at the cavity wall, (2) the cavity wall is tidally distorted into accretion streams consisting of near-ballistic gas parcels on eccentric orbits, (3) the portion of each stream moving inwards of an accretion horizon radius $\bar{r}\simeq a$ -the radius beyond which no material is returned to the cavity wall-becomes bound to a minidisk orbiting an individual binary component, and (4) the minidisk gas accretes onto the binary component through the combined effect of viscous and tidal stresses.

Keywords: Accretion, Hydrodynamical simulations, Binary stars, Black holes