Sazuna/UAT_keywords huggingface dataset:
An Update on the Future Flyby of Gliese 710 to the Solar System Using Gaia DR3: Flyby Parameters Reproduced, Uncertainties Reduced. Charting the near-future motion of known stars through the galaxy, none will pass closer to the Sun than Gliese 710. Here, we present an updated analysis of this upcoming flyby using Gaia DR3 data as well as the latest planetary ephemerides. Our new estimate reproduces the nominal values of those already published, but with reduced associated uncertainties. The distribution of distances of closest approach has a median value of 0.052 pc with a 90% probability of coming within 0.048-0.056 pc of the Sun; the associated time of perihelion passage is determined to be between 1.26 and 1.33 Myr with 90% confidence, with a most likely value of 1.29 Myr.

Keywords: Stellar kinematics, Solar system, Solar neighborhood
The Gravitational Redshift of Solar-type Stars from Gaia DR3 Wide Binaries. Light escaping from a gravitational potential suffers a redshift with magnitude proportional to the depth of the potential. This "gravitational redshift" is easily measurable in dense stars such as white dwarfs, but is much weaker and has evaded unambiguous detection in main-sequence stars. I show that the effect is directly measurable in the Gaia DR3 radial velocities (RVs) of the components of wide binary stars. In a sample of ~500 wide binaries containing a solar-type main-sequence star and a red giant or red clump companion, the apparent RV of the giant is on average 0.49 ± 0.02 km s-1 lower than that of the main-sequence star. This owes primarily to the giants' weaker gravitational fields and is in reasonably good agreement with the value expected from general relativity.

Keywords: Wide binary stars
A Search for T Tauri Stars toward Nearby, Dense Cores. We have searched 14 dense cores, 11 of which have literature distances of 150-350 pc, for T Tauri stars by using the Wide Field Grism Spectrograph 2 on the University of Hawaii 2.2 m telescope. As a result, we detected 50 Hα emission stars including 24 newly found objects. Twelve out of these 50 stars have a distance of ~190-370 pc, and 16 of them are within a distance of ~460 pc. Seven of these 16 objects are newly found Hα emission stars and would serve as new good targets for studying protoplanetary disks and young exoplanets.

Keywords: T Tauri stars, Young stellar objects, H-alpha stars, Molecular clouds
Great Refractor Domes: Pantheons of Astronomy. Height-to-diameter ratios of the enclosures of large refracting telescopes are contrasted with the classical domed structure of the Roman Pantheon. Enclosures whose domes do not sit upon a multi-storied drum, or atop an extended building complex, tend to evince a Pantheon-like ratio.

Keywords: History of astronomy, Optical observatories, Domes
Detection Feasibility of H<SUB>2</SUB> in Ultra-hot Jupiter Atmospheres. Ultra-hot Jupiters (UHJs) have recently been the focus of several atmospheric studies due to their extreme properties. While molecular hydrogen (H2) plays a key role in UHJ atmospheres, it has not been directly detected on an exoplanet. To determine the feasibility of H2 detection via transmission spectroscopy of the Lyman and Werner bands, we modeled UHJ atmospheres with H2 rotational temperatures varying from 2000 to 4000 K orbiting A-type stars ranging from T eff = 8500 K to T eff = 10,300 K. We present simulated transmission spectra for each planet-star temperature combination while adding Poisson noise varying in magnitude from 0.5% to 2.0%. Finally, we cross-correlated the spectra with expected atmospheric H2 absorption templates for each temperature combination. Our results suggest that H2 detection with current facilities, namely the Hubble Space Telescope, is not possible. However, direct atmospheric transmission spectroscopy of H2 may be viable with future UV-capable flagship missions.

Keywords: Exoplanet atmospheres, Transmission spectroscopy
Commotion in their Motions: Proper Motion Anomalies of Nearby AGB Stars. Proper motion anomalies (PMa) are often useful for identifying companions, but using this technique for large and luminous stars like Asymptotic Giant Branch (AGB) stars is problematic. We studied nearby AGB stars and their potential companions in a PMa catalog derived from Hipparcos and Gaia DR2 proper motion measurements. We found that companion configurations based on PMa for AGB stars are often implausible, such that the radius of the primary star is larger than the orbit of the putative companion. This may suggest an alternative origin of PMa in AGB stars, possibly surface brightness fluctuations due to their large convective surfaces.

Keywords: Asymptotic giant branch stars, Parallax, Proper motions
The Behavior of HgMn Stars in the Far UV-Paper 8: HR 7775. The analysis of 14 high resolution spectra of the chemically peculiar star HR 7775 recorded by the International Ultraviolet Explorer reveals large amplitude variations of the far and mid-ultraviolet flux (at minimum the flux is about 70% of its value at maximum) over the various observations with IUE. The lines at minimum flux are redshifted respect to their positions at maximum. These variations probably reflects an eclipse by a cooler and smaller companion of spectral type A or even early F. The absence of TESS observations prevents a search for periodic orbital and rotational variabilities.

Keywords: Chemically peculiar stars
A Meteor Spectroscopic Survey in the Nullarbor. We report the start of science operations of a meteor spectroscopic survey in the Nullarbor region, Western Australia. The observation program consists of well-proven observatories developed as part of the All-Sky Meteor Orbit System (AMOS) project. These comprise high-sensitivity all-sky imaging units, as well as spectroscopic instruments observing brighter meteors. They are co-located with Desert Fireball Network (DFN) instruments, which themselves provide high-resolution astrometry for fireballs. There are two goals for this program. One is to keep a constant watch on meteor activity by always having one AMOS sub-network in the dark. The second is to provide spectroscopic coverage for recovered meteorites by the DFN, establishing essential calibration points between meteoritic samples and fireball spectra.

Keywords: Meteorites, Fireballs, Spectroscopy
Fine-structure Excitation of O(<SUP>3</SUP>P) Induced by Collisions with Atomic Hydrogen. The utility of the far-infrared lines of oxygen as diagnostics of gas outflows and for other applications depends on accurate descriptions of the rate coefficients for excitation (and relaxation) through collisions with electrons and with hydrogen atoms. For O and H collisions, earlier calculations of rate coefficients show discrepancies leading to ambiguity in astrophysical applications. In this note we introduce a methodology that yields consistent sets of rate coefficients for a number of cases. We then apply our method to the O-H system in order to investigate the discrepancies. The present rate coefficients will be of particular interest for modeling observations of astrophysical environments in the far-infrared.

Keywords: Collision physics, Excitation rates, Atomic physics
Magnetic Fields in Low-mass Stars Increase Photometric Masses, Thereby Reducing Inferred Radius Inflation. Standard evolution models of a given age provide a relationship between stellar mass and T eff. Based on this, Cruz et al. have derived stellar masses and radii for a sample of Kepler stars using photometry alone: their radii are found to be inflated by up to 100% relative to standard models. However, magnetic fields distort the M-T eff relationship in a systematic way: here, we quantify this distortion, and show that radius inflations in the Cruz et al. stars are likely to be significantly smaller than 100%.

Keywords: Starspots, Stellar radii, Stellar magnetic fields
Evolution of Solar-type Activity: A Brief Study of Ca II Emission in Beta Hydri (G2 IV). We present results about the decrease of stellar activity for stars like the Sun evolving toward the subgiant stage. Specifically, we examine two-component chromosphere models (acoustic and magnetic) for β Hydri (G2 IV) based on detailed time-dependent simulations while focusing on Ca II emission. We convey models for two different photospheric magnetic filling factors.

Keywords: Stellar physics
Extinction of the TeV Gamma-Ray Background by sunlight. I show that pair production on sunlight introduces a sizable anisotropy in the cosmic background of TeV gamma-rays. The anisotropy amplitude in the direction of the Sun exceeds the cosmic dipole anisotropy from the motion of the Sun relative to the cosmic rest-frame.

Keywords: Gamma-ray astronomy
Period Variation of the Close Eclipsing Binary V405 Draconis. We found a period variation of the close binary of EW type V405 Draconis. From the O - C diagram built using survey data, data from the literature, and our observations, we calculated a period increase rate (1/P)(dP/dt) of 2.72(0.03) · 10-6 yr-1. Along with the monotonic period increase, TESS data demonstrates a sign of a cyclic variation of the period. We estimated the period of such cyclic variations as 537.9(1.4) days with a semi-amplitude of 0.00200(0.00001) days. This can provide evidence for the presence of the third body in the system.

Keywords: Close binary stars, Eclipsing binary stars, Astronomy data analysis
Hα and Continuum Sizes with the HST/WFC3 G141 GRISM: Outside-in Quenching for z = 1.0-1.4 Fast Quenchers. We investigate the evolution of the physical extent of star formation of M ⋆ &gt; 109 M ⊙ rapidly quenching galaxies at z = 1.0-1.4. We measure the galaxy Hα and stellar continuum sizes from their HST/WFC3 G141 grism spectroscopy and connect the galaxy sizes to time on their evolutionary delayed-τ tracks determined in Noirot et al. Most galaxies (10/13) have non-evolving Hα-to-continuum size-ratios consistent with unity within the measurement uncertainties, suggesting an homogeneous decline of star formation in these galaxies despite a rapid shut-down of their star formation. On the other hand, a handful (3/13) show statistically smaller Hα sizes compared to the stellar continuum as they age and approach the blue-cloud/red-sequence transition region. This suggests an outside-in shut-down of the star formation (potentially driven by environmental mechanisms) in these rapidly evolving galaxies as they move from the blue cloud toward the red sequence.

Keywords: Galaxy quenching, Galaxy spectroscopy, Galaxy evolution
Keck NIRES Spectral Standards for L, T, and Y Dwarfs. We present medium-resolution (λ/Δλ = 2700), near-infrared spectral standards for field L0-L2, L4, and L7-Y0 dwarfs obtained with the Near-Infrared Echellette Spectrometer on the Keck II 10 m telescope. These standards allow for detailed spectral comparative analysis of cold brown dwarfs discovered through ongoing ground-based projects such as Backyard Worlds: Planet 9, and forthcoming space-based spectral surveys such as the James Webb Space Telescope, SPHEREx, Euclid, and the Nancy Grace Roman Space Telescope.

Keywords: Brown dwarfs, Infrared spectroscopy, Standard stars, L dwarfs, Y dwarfs, Spectroscopy, T dwarfs
The Closest Past Flyby of a Known Star to the Solar System: HD 7977, UCAC4 237-008148 or WISE J072003.20-084651.2?. It is argued that the closest past flyby of a known star to the solar system was that of Scholz's star (WISE J072003.20-084651.2). Here, we show that the distribution of distances of closest approach of this star has a median value of 0.330 pc with a 90% probability of coming within 0.317-0.345 pc of the Sun; the associated time of perihelion passage is determined to be between 78.6-81.1 kyr ago with 90% confidence, with a most likely value of 79.9 kyr. Using Gaia DR3 data and the latest planetary ephemerides, we found that UCAC4 237-008148 (RUWE = 0.927) approached even closer with a median perihelion distance of 0.259 pc and a 90% confidence interval of 0.249-0.269 pc, 1.158 Myr ago. HD 7977 might have passed 0.15 pc from the Sun 2.77 Myr ago, but it has RUWE = 2.015.

Keywords: Stellar kinematics, Solar system
Approximate Relation Between Integral Albedo and Single-scattering Albedo of the Particulate Media. The radiative transfer model makes it possible to establish relationships between the single scattering albedo and the integral albedo of a medium consisting of particles. In this paper, an approximation is proposed for solving the inverse problem-calculating the albedo of a single scattering of a particle, based on the known value of the integral albedo. This approximation can be useful to all researchers involved in the photometry of solar system bodies with regolith-like surfaces.

Keywords: Radiative transfer
The Behavior of HgMn Stars in the Far UV-Paper 9: HD 21933. The analysis of 18 high resolution spectra of the chemically peculiar star HR 1079 recorded by the International Ultraviolet Explorer reveals large amplitude variations of the far ultraviolet flux (about 80% flux decrease at minimum compared to maximum) over the various observations with IUE. These variations could reflect the presence of spots over the surface of HD 21933. The TESS lightcurve of HD 21933 has a complex structure which resembles a double sine structure. The time intervals separating successive minima are not constant but range from 1.16 to 1.32 ± 0.03 days.

Keywords: Chemically peculiar stars
Chemical Abundances for 25 JWST Exoplanet Host Stars with KeckSpec. Using a data-driven machine learning tool we report T eff, $\mathrm{log}(g)$ , $v\sin (i)$ , and elemental abundances for 15 elements (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, Y) for a sample of 25 exoplanet host stars targeted by JWST's first year of observations. The chemical diversity of these stars show that, while a number of their companion planets may have formed in a disk with chemistry similar to Solar, some JWST targets likely experienced different disk compositions. This sample is part of a larger forthcoming catalog that will report homogeneous abundances of ~4500 FGK stars derived from Keck/HIRES optical spectra.

Keywords: High resolution spectroscopy, Exoplanet atmospheric composition , Astrometric exoplanet detection, Chemical abundances, Exoplanet astronomy
The Effect of Metallicity on the Formation of Massive Black Holes through Stellar Collisions in Young Massive Star Clusters. Dynamical interactions facilitated by the high densities in massive star clusters can lead to large numbers of stellar collisions and unique stellar evolution pathways not possible for stars evolving in isolation. Using N-body cluster models, we study the role of stellar collisions in the formation of massive black holes, specifically studying the effect of stellar metallicity on this process. We show that at high metallicity (up to solar), the number of massive black holes formed may be reduced by up to a factor of ten compared to low-metallicity clusters. We also examine the role of collisions in the production of pair-instability supernovae and predict event rates of these transients in the local universe.

Keywords: Globular star clusters, Young star clusters, Supernovae, Astrophysical black holes
The Negative Polarization Branch of Asteroid 47 Aglaja. The degree of linear polarization of the main-belt asteroid 47 Aglaja was measured at low phase angles. The data obtained made it possible to construct a complete branch of the negative polarization. Comparison with asteroids of the same spectral type and having equally high albedo values showed that asteroid 47 Aglaja has a much smaller negative polarization branch, which indicates a possible difference in the chemical composition or structure of matter on the surface.

Keywords: Polarimetry, Asteroids
Sudden Dimming of the Symbiotic Mira HM Sge. The Symbiotic Mira HM Sge has dimmed considerably over the last year, beyond what is expected of its pulsation-related variability. HM Sge is composed of a cool oxygen-rich AGB star accreting onto a hotter white dwarf companion. The system brightened 6 mag in the optical in 1975 as a result of a Nova-like outburst. It has since dimmed and plateaued in the visible, while gradually growing in brightness in the near-IR over the past 15 yr (0.092 mag yr-1). Within the last year, however, the brightness has dropped by 1.52 mag in the I-band. While the system is expected to be near its pulsation minimum, the brightness is below the values expected of the last three pulsation cycles, and appears independent of the system's fundamental mode pulsations. We suspect this may be the result of a change in the orientation of the system or episodic mass loss.

Keywords: Asymptotic giant branch, Stellar mass loss, Mira variable stars, Symbiotic novae, Symbiotic binary stars
How to Become a Mini-moon: Some Hints from 2022 NX<SUB>1</SUB>. Low-velocity encounters between our planet and any near-Earth object (NEO) in an Earth-like orbit may induce its temporary capture as a mini-moon. Such mini-moon episodes could lead the NEO to complete one or more revolutions around Earth when gravitationally bound, a temporarily-captured orbiter, like in the cases of 2006 RH120 and 2020 CD3; sometimes not even one revolution is completed, a temporarily-captured flyby, like in the case of 1991 VG. Asteroid 2022 NX1 experienced a temporarily-captured flyby in 1981, has had another one in 2022, and will become a temporarily-captured orbiter in 2051. This object occupies the edge of Earth's co-orbital space and sometimes it approaches us following a horseshoe path.

Keywords: Solar system, Asteroids
Ten-micron Emission in a Color-magnitude Diagram of M Giant Variables. Infrared color-magnitude diagrams are presented for variable M giants within the Two-Micron Sky Survey for which 10 μm dust emission was detected in IRAS low-resolution spectra. Dust emission is mostly limited to a definable region in absolute M  Ks  magnitude and (J - K  s ) color, and to pulsation periods greater than 50 days.

Keywords: Infrared photometry, Stellar mass loss
UV Slopes at All Redshifts Are Consistent with H = 1 Stochastic Star Formation Histories. Multiple investigations support describing galaxy growth as a stochastic process with correlations over a range of timescales governed by a parameter, H, empirically and theoretically constrained to be near unity. Here, we show that the distribution of UV-slopes, β, derived from an ensemble of theoretical H = 1 star formation histories is consistent with data at all redshifts z ≤ 16. At z = 0, the median value &lt;β  H=1&gt; = - 2.27 agrees well with the canonical β 0 = -2.23 for local starbursts. At 4 ≲ z ≲ 16, JWST data span the model distribution's 2nd to 98th percentiles. Values of -2.8 ≤ β ≤ -2.5 should be common in early galaxies without reference to exotic stellar populations-arising solely from a null hypothesis of H = 1 for the underlying diversity of galaxy growth histories. Future data should be interpreted with this fact in mind.

Keywords: Galaxy formation, High-redshift galaxies
Catalog of X-Ray Detected Be Stars (XDBS). We present a catalog of X-ray Detected Be Stars (XDBS) with 161 Be stars from the Be Star Spectra (BeSS) database having X-ray counterparts in the Chandra Source Catalog v2.0, XMM-Newton 4XMM-DR11 Catalog, or Swift 2SXPS Catalog. The multi-wavelength catalog includes accurate optical positions, X-ray properties (fluxes, photon indices and hardness ratios), optical, near-infrared and infrared photometry, source classifications (when available), and other properties including proper motions, effective temperatures, X-ray to optical flux ratios as well. We also provide a convenient graphical user interface which allows for easy visualization of the catalog content.

Keywords: Be stars, X-ray binary stars, Catalogs, X-ray stars
Long-term Variability of Non-radial Pulsations in SXP 4.78. OGLE I-band observations for [M2002] SMC 20671, the optical counterpart of SXP 4.78, were searched for periodicities with P &gt; 0.5 days. Three sets of photometric signals were detected, which are attributed to non-radial pulsations of the Be star. All signals show considerable variability in power over the 16 seasons studied. The most likely periods of the NRPs are 0.5826, 0.6164, and 0.6424 days.

Keywords: Be stars, X-ray binary stars
Search for Extended Sources in the Images from Chandra X-Ray Observatory Advanced CCD Imaging Spectrometer. We present a convenient tool (ChaSES) which allows to search for extended structures in Chandra X-ray Observatory Advanced CCD Imaging Spectrometer images. The tool relies on DBSCAN clustering algorithm to detect regions with overdensity of photons compared to the background. Here we describe the design and functionality of the tool which we make publicly available on GitHub. We also provide online extensive examples of its applications to the real data.

Keywords: Astronomy data reduction, Astronomy data visualization, Astronomy data analysis, Astronomy image processing
The Behavior of HgMn Stars in the Far-UV-Paper 10: HD 174933A and HD 35548A. The analysis of low and high resolution spectra of the chemically peculiar stars HR 7113 and HR 1800 recorded by the SWP camera on board the International Ultraviolet Explorer reveals no variations of the far-ultraviolet flux for spectra separated by 4 months and 3 days for HR 7113 and 1 day apart for HR 1800 respectively. The TESS lightcurve of HR 7113 suggests a period close to 6.46 days which is close to the orbital period previously determined. For HR 1800, a clear period is not seen, time intervals between successive maxima range from 5.53 to 5.82 days.

Keywords: Chemically peculiar stars
Extension of the Asfgrid for Correcting Asteroseismic Large Frequency Separations. The asteroseismic scaling relation, Δν ≈ ρ 0.5, linking a star's large frequency separation, Δν, and its mean density, ρ, is not exact. Yet, it provides a very useful way to obtain fundamental stellar properties. Common ways to make the relation more accurate is to apply correction factors to it. Because the corrections depend on stellar properties, such as mass, T eff, and metallicity, it is customary to interpolate these properties over stellar model grids that include both Δν, measured from adiabatic frequencies of the models, and the models' stellar density; hence linking both sides of the scaling relation. A grid and interpolation tool widely used for this purpose, known as Asfgrid, was published by Sharma &amp; Stello. Here, we present a significant extension of Asfgrid to cover higher- and lower-mass stars and to increase the density of grid points, especially in the low-metallicity regime.

Keywords: Stellar astronomy, Galactic archaeology, Asteroseismology
Limb-darkening Coefficients for the Filter CBB. The CBB filter is particularly appropriate for exoplanet differential photometry using smaller (≤1.0 m) telescopes for two primary reasons. First, the CBB filter provides far greater throughput than standard filters (i.e., 92% throughput for CBB compared to 19% for V), which results in significantly greater measurement precision. Second, the CBB significantly reduces the size of air-mass curvature systematic error (8 mmag/airmass for a CBB filter compared to 59 mmag/airmass for a clear filter). In this Research Note we provide the theoretical calculations of the limb-darkening coefficients (LDCs) for the filter CBB adopting the two most used bi-parametric laws: quadratic and power-2 laws. The calculations of LDCs were carried out adopting the ATLAS stellar atmosphere models, plane-parallel version. These grids cover 19 metallicities ranging from 10-5 up to 10 +1 solar abundances, 0 ≤ log g ≤ 5.0 and 3500 K ≤ T eff ≤ 50,000 K (9586 models).

Keywords: Stellar atmospheres