Sazuna/UAT_keywords huggingface dataset:
The Abundance of Phosphorus in the HgMn Star 14 Sge. The abundances of several elements in the atmosphere of the HgMn star 14 Sge (HR 7664) are derived from the analysis of high-resolution spectra obtained recently with the spectropolarimeter NeoNarval. A large phosphorus overabundance, about 60 times the solar abundance, is found. This study is the beginning of a systematic survey of all northern HgMn stars aiming at deriving their abundances in a consistent manner.

Keywords: Chemically peculiar stars
The CARMA-NRO Orion Survey—Data Release. With this research note, we are releasing the CARMA-NRO Orion Survey data first presented in Kong et al., enhanced with additional coverage of the L1641-C region to the south of the integral-shaped filament. We are including position-position-velocity cubes for the molecular lines 12CO(1-0), 13CO(1-0), and C18O(1-0). The original paper includes details of the data reduction and final sensitivity. The mapped region now spans about 2°5 along the Orion A cloud in the north-south direction, providing an unprecedented overview of the extended molecular gas. The associated data cubes are publicly available on the Harvard Dataverse 10.7910/DVN/6Q26PN (Version 3). Kong et al. and this research note should be cited when using these data.

Keywords: Astronomy databases, Stellar wind bubbles, Millimeter astronomy, Star forming regions, Massive stars, Stellar jets, Molecular clouds, Photodissociation regions, Young stellar objects, Star formation, Interstellar medium, Radio astronomy
Photometric Redshifts in the W-CDF-S and ELAIS-S1 Fields Based on Forced Photometry from 0.36 to 4.5 Microns. The W-CDF-S and ELAIS-S1 fields will be two of the LSST Deep Drilling fields, but the availability of spectroscopic redshifts within these two fields is still limited on deg2 scales. To prepare for future science, we use EAZY to estimate photometric redshifts (photo-zs) in these two fields based on forced-photometry catalogs. Our photo-z catalog consists of ∼0.8 million sources covering 4.9 deg2 in W-CDF-S and ∼0.8 million sources covering 3.4 deg2 in ELAIS-S1, among which there are ∼0.6 (W-CDF-S) and ∼0.4 (ELAIS-S1) million sources having signal-to-noise ratio (S/N) &gt;5 detections in more than 5 bands. By comparing photo-zs and available spectroscopic redshifts, we demonstrate the general reliability of our photo-z measurements. Our photo-z catalog is publicly available at 10.5281/zenodo.46031780

Keywords: Surveys, Extragalactic astronomy, Catalogs
Mid-infrared Detections of Type I Supernovae and Unclassified Possible Supernovae with NEOWISE. We describe 238 mid-infrared detections of supernovae and 195 possible supernovae in co-added images of the NEOWISE mission. We find one type Ia supernova (SN 2015cp), which has a mid-infrared evolution that is similar to known type Ia with long-lived mid-infrared detections. We also find long-lived mid-infrared detections in one type Ic (SN 2017dio) and one type Ib (SN 2016ajo). Additionally we provide measured magnitudes for most of our detections. We also find two transients, which we suspect to be TDEs: ASASSN-18ap and ATLAS17jrp.

Keywords: Type Ic supernovae, Type Ib supernovae, Tidal disruption, Type II supernovae, Massive stars, Infrared astronomy, Circumstellar matter, Type Ia supernovae, Infrared sources
Detection of the Hg II Line at 3983.93 Å in One Optical Spectrum of Maia. Evidence is reported for the first time for the presence of the Hg II line in a Narval I profile of Maia, the fourth brightest member of the Pleiades open cluster. The Hg II line in Maia absorbs about 2% of the local continuum and can be reproduced with an overabundance of mercury of about 4000 times the solar mercury abundance. This line is probably variable suggesting that mercury might be distributed in spot(s) over the surface of Maia. Maia is currently classified as a He-weak Mn star, it should probably be reclassified as a HgMn star.

Keywords: Mercury-manganese stars, Chemically peculiar stars
Change in the Radio Structure and Position of the Quasar CTA 21. Astrometric positions of radio-emitting active galactic nuclei (AGNs) can be determined with sub-milliarcsec accuracy using very long baseline interferometry (VLBI). The usually small apparent proper motion of distant extragalactic targets allow us to realize the fundamental celestial reference frame with VLBI observations. However, long-term astrometric monitoring may reveal extreme changes in some AGN positions. We present the case of CTA 21 whose position gradually shifted by ∼0"04 over two decades. By comparing archival VLBI images from 1996 and 2018, we show that its radio structure changed substantially, likely causing the apparent positional shift.

Keywords: Extragalactic radio sources, Active galactic nuclei, Radio astrometry, Very long baseline interferometry
AT2020caa: A Type Ia Supernova with a Prior Outburst or a Statistical Fluke?. We recently discovered an extragalactic transient, AT2020caa, from the Zwicky Transient Facility alert stream using the community broker ANTARES. This transient apparently exhibited two outbursts within one year (between 2020 and 2021). Based on a decade-long historical light curve of the candidate host galaxy, we rule out activity from the galaxy nucleus to explain these outbursts. The measured peak magnitudes (assuming the known spectroscopic redshift of the candidate host galaxy) put AT2020caa in the realm of thermonuclear supernovae (SNe) or luminous core-collapse SNe. A handful of the latter are known to show prior outbursts (POs), thought to be linked to mass loss in massive stars. Using Gemini/GMOS, we obtained a spectrum of the current outburst that shows it to be a Type Ia supernova. We examine the nature of AT2020caa's PO seen a year earlier and conclude that it is likely a separate SN within the same galaxy.

Keywords: Supernovae
Searching for Extragalactic Star Formation in the M101 Group. We present deep, narrowband imaging of the nearby spiral galaxy M101 to search for star-forming dwarf galaxies and isolated H II regions in the group environment. Isolated star-forming regions, unassociated with spiral arms, probe star formation (SF) at the lowest masses and environmental densities. Such objects may be isolated star-forming events or ongoing evidence of tidal interactions. Using the Burrell Schmidt telescope, we target the brightest emission lines of star-forming regions, Hα, Hβ, and [O III], to detect potential isolated regions. Great care was taken to remove potential source contaminants, such as high-redshift objects and Galactic M stars, from our source list. For each detected source, we compare the emission line fluxes and equivalent widths, along with structural and photometric properties, to samples of Local Group dwarfs and star-forming galaxies in the SINGG/11HUGS samples. We discuss our findings in the context of SF in low-density environments and evolution of the M101 Group.

Keywords: Galaxy evolution, Star forming regions, Star formation, Narrow band photometry
The Power Spectrum of Episodic Stellar Mass Accretion. The process by which stars accumulate their mass is episodic, characterized by long-duration low-accretion phases punctuated with intense accretion bursts. The bursts are several orders of magnitude greater in accretion rate and contribute a significant fraction of the total mass. In this article we present results of performing a time series analysis using the Fourier transform on a computer simulation of the burst mode of mass accretion. We find that the most prominent peaks in the power spectrum correspond to characteristic timescales of several thousand years.

Keywords: FU Orionis stars, T Tauri stars, Young stellar objects, Star formation, Circumstellar disks
The Roman Space Telescope Relative Calibration System and the Dark Energy Figure of Merit. One of the Roman Space Telescopes principal science objectives is to measure dark energy's equation-of-state using a strategic combination of imaging and spectroscopic surveys at high galactic latitude. Type Ia Supernovae survey requirements demand 0.3% photometric accuracy and calibration of key systematic effects. One of these is count rate dependent nonlinearity (CRNL) that if uncorrected affects the accuracy of SNe Ia distance measurements. Romans Relative Calibration System (RCS) enables on-orbit measurement and tracking of CRNL, through a direct illumination mode and a simultaneous lamp plus scene mode. We present results on the impact of CRNL calibration on the dark energy figure of merit (FoM), for a specific reduction of RCS capabilities. We examined many combinations of illumination and passbands, finding that only six meet the requirements. No RCS at all results in a factor of 5 degradation in the FoM.

Keywords: Cosmology, Calibration, Type Ia supernovae
E+A Galaxies in and Around Nearby Rich Clusters of Galaxies. We have spectroscopically identified 600 new E+A galaxies and candidates across 16 fields totaling roughly 480 square degrees in the Sloan Digital Sky Survey. E+A galaxies are post-starburst systems that have undergone a significant burst of star formation within the past 1-2 Gyr and are now fully quenched. They comprise a small population that is key to understanding the transition from star-forming to quiescent galaxies. Our survey focused on four nearby rich clusters of galaxies and their surroundings: Virgo, Coma, Leo, and Hercules. 356 candidates were identified in the clusters, and an additional 244 were identified in control fields or otherwise outside cluster bounds. Understanding the distribution and dynamics of the E+As has the potential to shed light on the evolutionary mechanisms present within nearby cluster environments. In this note, we give a brief overview of our selection processes and locations, and report on ongoing analyses of the sample.

Keywords: Galaxy clusters, Quenched galaxies, E+A galaxies, Galaxy evolution, Galaxy quenching, Post-starburst galaxies
Dust in Comet 67P/Churyumov-Gerasimenko: Interrelation between in situ Findings by Rosetta and Ground-based Polarimetry. We present a comprehensive model of the ground-based polarization observations from comet 67P/Churyumov-Gerasimenko using two different apertures on its apparitions of 1982 and 2016. Our modeling suggests that the dust composition viewed within the two apertures is the same, but that they have different size distributions, with smaller particles more concentrated in the innermost coma. The best fits to the measurements using the smallest aperture are obtained using a dust size distribution similar to the Rosetta findings. Furthermore, the model parameters providing the best fit to polarimetric observations using the large aperture appear remarkably consistent with what was previously inferred in other comets. This represents an attempt to reconcile the Rosetta results with ground-based observations.

Keywords: Comets, Short period comets, Coma dust
Star and Solar System Maps: A History of Celestial Cartography. Since antiquity, people have observed the night sky. To establish order and predictability, people made maps of the heavens. Two kinds emerged. The first were star maps, organized into constellations but focused on stellar location in the sky. Stars were placed in a coordinate system, initially based on celestial latitude and longitude oriented to the ecliptic, but later based on decl. and R.A. oriented to the celestial equator. Over time, telescopic and scientific needs called for more detailed coordinate systems, and constellation images disappeared. The second kind of heavenly map depicted the solar system and focused on planetary locations and surface characteristics. For many centuries, these were cosmological diagrams with concentric planetary and stellar circles, centered first on the Earth and then the Sun. Now such maps have no stellar boundary, and ever larger telescopes and space probes allow us to view planetary surfaces in unprecedented detail.

Keywords: History of astronomy
A Highly Collimated Flow from the High-mass Protostar ISOSS J23053+5953 SMM2. We present Very Large Array cm continuum observations, as well as 1.3 mm continuum and CO(2-1) observations taken with the Submillimeter Array toward the high-mass protostellar candidate ISOSS J23053+5953 SMM2. Compact cm continuum emission was detected near the center of the SMM2 dust core, and the 1.3 mm thermal dust emission indicates a core mass of 46 M⊙. The CO(2-1) observation revealed a large, massive molecular flow centered on the SMM2 core. This fast outflow (&gt;50 km s-1) appears highly collimated, with a broader, lower-velocity component. The large values for outflow mass (45 M⊙), and energetics derived are consistent with those of flows driven by high-mass YSOs. The dynamical timescale of the flow is between 1.5-7.2 × 104 yr. Our data confirm previous findings that SMM2 is an emerging high-mass protostar in a very early phase of evolution, with an ionized jet, and a fast, highly collimated, and massive outflow.

Keywords: Stellar jets, Star formation
Practical Effects of Integrating Temperature with Strang Split Reactions. Many astrophysical environments involve convective or explosive flows driven by thermonuclear reactions (Type Ia supernovae, classical novae, X-ray bursts, stellar evolution). Simulation codes need to accurately capture the interactions between reactions and hydrodynamics to produce realistic models of these events. For astrophysical reacting flows, operator splitting is commonly used to couple hydrodynamics and reactions. Each process operates independent of one another, but by staggering the updates in a symmetric fashion (via Strang splitting) second order accuracy in time can be achieved. However, approximations are often made to the reacting system, including the choice of whether or not to integrate temperature with the species. Here we demonstrate through a simple convergence test that integrating an energy equation together with reactions achieves the best convergence when modeling reactive flows with Strang splitting. Additionally, second order convergence cannot be achieved without integrating an energy or temperature equation.

Keywords: Nucleosynthesis, Hydrodynamics, Computational methods, Nuclear astrophysics, Astrophysical fluid dynamics, Astronomical simulations
Interstellar Highly Ionized Species toward Cygnus: A Closer Look. We examine Hubble Space Telescope (HST)/STIS data, complemented with International Ultraviolet Explorer (IUE) data, to delineate interstellar absorption of highly ionized species, C IV, Si IV, and N V, and low ionization species toward four stars in Cygnus. Previous IUE studies indicate two major velocity complexes for C IV and Si IV extending across Cygnus. We see interstellar N V in HST/STIS data for HD 190918 and Cyg X-1. In both stars, the N V is at the velocities of interstellar C IV and Si IV. In HD 190918, the N V is weak, possibly due to enhanced X-ray ionization produced by this binary system. The Cyg X-1 data are of low signal-to-noise, but N V is quite strong with a small b-value, indicating N V arises in a cooler H II region resulting from X-ray Auger ionization by Cyg X-1.

Keywords: Ultraviolet astronomy, Interstellar absorption, H II regions
A New Look into K-giants' Chromospheres. We report the preliminary modeling of archival Center for High Angular Resolution Astronomy (CHARA)/Visible spEctroGraph and polArimeter interferometric data of a K-giant star using the PHOENIX atmosphere code. We find that our preparatory model that includes only the chromospheric contribution closely reproduces the observed infrared Ca II triplet line profiles of a test star: the K-giant, β Cet. This preliminary work requires the additional modeling of the wind contribution to improve the agreement with observations. We plan to perform a systematic study of K-giants chromospheric emission with multi-wavelength and multi-technique observations and modeling. Our plans include extending the modeling work to include the underlying wind component for a larger set of stars. Stellar Parameters and Images with a Cophased Array, the second-generation instrument at CHARA, will be the ideal instrument to perform such observations and reveal the chromospheric activity of K-giants.

Keywords: Optical interferometry, Astronomy data modeling, Late-type stars, Evolved stars, K giant stars, K stars, Astronomy data analysis, Stellar mass loss, Stellar winds, Interstellar medium, Late-type giant stars, Giant stars
Extending a Grid of Hydrodynamic Planetary Upper Atmosphere Models. In this research note, we outline the extension of the grid of upper atmosphere models first presented in Kubyshkina et al. The original grid is based on a 1D hydrodynamic model and consists of about 7000 models covering planets of a size ranging from that of Earth to twice that of Neptune at orbits corresponding to equilibrium temperatures between 300 and 2000 K around solar-like (0.4 to 1.3 solar mass) stars. The extended and revised grid of models consists of 10,235 points and covers a planetary mass range of up to 109 Earth masses, which allows one to outline the transition between low- and high-gravity hot planets in in short period orbits. We prepared the interpolation tool allowing one to use the grid to define the mass-loss of a planet that falls into the parameter range of the grid. We provide a comparison of our results to common analytical models.

Keywords: Hydrodynamical simulations, Upper atmosphere, Hydrodynamics, Exoplanet atmospheric variability, Exoplanet atmospheres
Opacity Changes from Engulfed Material. Engulfment of several bulk earthlike planets makes only a small effect on the stellar opacity for a sunlike star.

Keywords: Stellar atmospheric opacity, Chemical abundances, Exoplanets
Identification of a Low-mass Companion to the White Dwarf SDSS J131730.84+483332.7. We present the discovery of 2MASS J13173072+4833343, a low-mass stellar companion to the ∼5.5 Gyr old white dwarf SDSS J131730.85+483332.8. This companion was discovered through the Backyard Worlds: Planet 9 citizen science collaboration. We obtained a near-infrared spectrum of the companion and determined a spectral type of M8.5. Using the cooling age of the white dwarf, we determined that the stellar companion has a mass of ${0.077}_{-0.017}^{+0.005}$ M⊙, or ${80.2}_{-1.8}^{+0.5}$ MJup, near the substellar boundary.

Keywords: Binary stars, Substellar companion stars
Significant Improvement in Planetary System Simulations from Statistical Averaging. Symplectic integrators are widely used for the study of planetary dynamics and other N-body problems. In a study of the outer solar system, we demonstrate that individual symplectic integrations can yield biased errors in the semimajor axes and possibly other orbital elements. The bias is resolved by studying an ensemble of initial conditions of the outer solar system. Such statistical sampling could significantly improve measurement of planetary system properties like their secular frequencies. We also compared the distributions of action-like variables between high and low accuracy integrations; traditional statistical metrics are unable to distinguish the distribution functions.

Keywords: Exoplanet dynamics, Celestial mechanics, Computational methods, Galaxy dynamics
Gas Evolution in Inner Disk Cavities from a Synergic Analysis of IR-CO and UV-H<SUB>2</SUB> Spectra. We are conducting a multi-wavelength analysis of high-resolution molecular spectra that probe the evolution of gas in the inner 10 au in protoplanetary disks. A sample of 15 disks has been combined to probe a range of inner disk structures including small and large dust cavities. Half of the sample has been observed in far-ultraviolet H2 emission with a new HST-COS program (GO-14703), that we have combined to near-infrared spectra of CO emission as observed with VLT-CRIRES and IRTF-iSHELL. This synergic dataset traces the evolution and depletion of CO and H2 in inner disk cavities and shows an evolving radial stratification of the molecular gas, where CO lines are narrower than H2 lines in disks with cavities. CO rotation diagrams also show significant evolution, suggesting a change in gas excitation as CO emission recedes to larger disk radii.

Keywords: Molecular gas, Molecular spectroscopy, Ultraviolet astronomy, Pre-main sequence stars, Protoplanetary disks, Circumstellar disks, Exoplanet formation, Near infrared astronomy
An IRTF-iSHELL Survey of 4.52-5.25 μm CO Spectra in Protoplanetary Disks of Intermediate-mass Stars: Preliminary Sample and Analysis. We are conducting a survey of high-resolution near-infrared CO rovibrational spectra in protoplanetary disks around young intermediate-mass stars. We use IRTF-iSHELL with the 0"375 and 0"75 slits, providing 4 km s-1 and 6 km s-1 resolution and covering 4.52-5.25 μm in one single exposure. This includes part of the rovibrational R branch and most of the P branch of the CO fundamental band (Δv = 1), one of the best tracers of warm/hot gas in disks. The high quality of the spectra and the large sample covered in this survey will support multiple investigations to study the structure, kinematics, composition, and evolution of the inner 10 au in disks for years to come. The survey currently includes ∼30 stars mostly within 200 pc, complementing extensive imaging campaigns that are observing their disks at optical, infrared, and millimeter wavelengths and revealing structures and planets.

Keywords: Molecular gas, Molecular spectroscopy, Planetary system formation, Infrared astronomy, Protoplanetary disks, Circumstellar disks, Planet formation
The Rapid Far-ultraviolet Variability of Maia Recorded by IUE. Evidence is presented that the far ultraviolet flux of Maia recorded by the International Ultraviolet Explorer is variable over a timescale of a few hours. In contrast, the radial velocity of the Si II doublet near 1530 Å does not vary on short timescales.

Keywords: Chemically peculiar stars
Conditions for Superwind Classes of Super Star Clusters. Mechanical feedback from young massive stars in super star clusters contributes to the formation of superwinds and superbubbles in star-forming regions. We conduct hydrodynamic simulations using the non-equilibrium ionization package MAIHEM to explore how outflow velocity, mass-loading, metallicity, and ambient density can affect the occurrence of catastrophic cooling. To predict optical and UV emission lines, we apply the photoionization code CLOUDY to the physical conditions predicted by our hydrodynamic simulations. Our results could be useful for characterizing catastrophic cooling in starburst regions like the nearby Green Peas and distant star-forming galaxies.

Keywords: Starburst galaxies, Cooling flows, Hydrodynamics, Star forming regions, Superbubbles
Preliminary Results of Virtual Reality Mapping of E+A Galaxies and Candidates in Nearby Rich Clusters of Galaxies. In the study of large astronomical data sets, virtual reality (VR) can help build valuable spatial intuition for scientific discovery. We created VR visualizations of E+A galaxies and candidates in four nearby clusters of galaxies: Leo, Virgo, Hercules, and Coma. E+A's are a type of post-starburst galaxy in which all star formation has been recently (∼1 Gyr ago) quenched. Our E+A samples were assembled and cataloged by the Y/Dim collaboration through visual and quantitative analysis of SDSS DR16 spectra. The visualizations are designed for Oculus VR headsets, and utilize C# scripts which interface with the Unity engine, including public domain code and code developed by the lead author. We use these visualizations to find features of the aforementioned galaxy clusters: for instance, a "nose" of low velocity objects in the center of the Virgo cluster and a collection of E+A candidates along a galactic filament in the Coma cluster.

Keywords: Galaxy clusters, Astronomy software, Virgo Cluster, Coma Cluster, E+A galaxies, Galaxy evolution, Galaxy quenching, Post-starburst galaxies