Sazuna/UAT_keywords huggingface dataset:
To Explode or Not Explode? An Analysis of the Explodability of Binary and Single Stars. Most massive stars in our universe are born in binary systems, and yet their fates are quite uncertain, due to a poor understanding of their evolution. It is well known, however, that the density profile of a collapsing core, particularly at the interface between silicon and oxygen shells, is important when determining the explodability of a star. While this has been studied for single stars, it has been rarely studied for binary stars. In this note, we explore the explodability of single and binary stars using self-consistent supernova simulations. We study the differences in the silicon–oxygen interface and compactness of the progenitor stars and how they affect the explodability. We find that binary-stripped stars with initial masses above 37 M⊙ are not as explodable as their single-star counterparts.

Keywords: Binary stars, Supernovae, Core-collapse supernovae
Mock JWST Colors of Two Different Star Formation Histories at z ~ 4. In this work, we test if JWST NIRCam filters can distinguish between two different galaxy star formation histories (SFHs) at z = 3–4. We use the Code Investigating GALaxy Emission to model F150W, F277W, and F770W-band magnitudes for mock massive galaxies at 3.5 &lt; z &lt; 4.5 generating two different SFHs: (1) a delayed-τ, analogous to a starburst-like galaxy with a mostly uniform stellar population, and (2) a decayed exponential with a late burst to represent a more even mixture of old and young stellar populations. We explored the F277W ‑ F770W versus F150W ‑ F277W color space, and determined that the delayed-τ SFH produces highly clustered, relatively "flat" colors in both planes; whereas the other SFH produces more diversity across this color space. This work motivates further studies on the potential for JWST colors to rapidly identify varying evolutionary pathways for galaxies at z = 3–4.

Keywords: Starburst galaxies, Galaxy colors, Two-color diagrams
Discovery of Raman-scattered C II Lines in V366 Carinae with GHOST/Gemini South. We report the detection of Raman-scattered C II lines at 7023 and 7054 Å in the symbiotic star V366 Carinae using Gemini High-resolution Optical SpecTrograph (GHOST) at Gemini South. These faint features, originating from the C II doublet at λλ1036 and 1037, are rare and have been detected in only two other symbiotic stars: V1016 Cygni and RR Telescopii. Our findings showcase the exceptional sensitivity of GHOST to detect subtle spectral features and open the door to comparative studies of Raman-scattered C II features across these systems.

Keywords: High resolution spectroscopy, Symbiotic binary stars, Stellar spectral lines
Determination of the Abundance of Mercury from the Hg II Line at 5677.10 Å in Late B-type Stars. XI. HD 11753 (ϕ Phe). The weak line of Hg II located at 5677.10 Å is not detected in a coadded HARPS spectrum of the HgMn star HD 11753 which may be explained by the moderate excess of mercury in this star compared to other HgMn stars. The synthesis of the 4400–4600 Å spectral range yields several new measurements of the abundances of helium, magnesium, aluminum, silicon, titanium, chromium, manganese, iron, nickel and platinum. These new measurements agree well with previous measurements. The synthesis of the Pt II line at 4514.14 Å, yields a first measurement of a large excess of platinum (+3.74 dex) in HD 11753.

Keywords: Chemically peculiar stars, Manganese stars
The Symbiotic Star V694 Mon has Transitioned from the Accreting-only State to the Steady Burning Phase. I propose that the drastic photometric and spectroscopic changes affecting the symbiotic star V694 Mon since 2018, are due to its transition from the accreting-only state to steady hydrogen-burning on the surface of the white dwarf (WD), closely mimicking the pattern followed by V4368 Sgr. The phase of peak optical brightness and weakest emission lines has probably been reached in early 2024. The high-velocity absorptions powered by jet-ejection and the wild flickering, which dominated the century-long quiescence, should not reappear as long has nuclear burning will hold (timescale of decades). The 3500 L⊙ burning luminosity suggests a 0.60 M⊙ mass for the WD.

Keywords: Hydrogen burning, Symbiotic binary stars, Stellar accretion, Classical novae
Zeeman Spectral Line Fitting. The Zeeman effect plays a pivotal role as an observational technique for directly assessing the magnitude of magnetic fields within star-forming regions. Over time, Zeeman effect analysis has primarily relied upon software tools such as the Astronomical Image Processing System and MIRIAD. These tools necessitate manual involvement in the analysis and line fitting processes. This study delves into two potential automated methodologies for Zeeman analysis: one grounded in a least squares framework and the other embracing the maximum-likelihood approach. Our investigation reveals that the utilization of Markov Chain Monte Carlo, anchored in the maximum-likelihood framework, results in improved spectral line fitting outcomes with more favorable residuals. Concluding our efforts, we have encapsulated the automated analysis procedure within a software package, called Zeeman_modelling, installable through pip, accompanied by a straightforward command-line interface.

Keywords: Computational astronomy, Zeeman-Doppler imaging, Bayesian statistics, Astronomy software
The γ-Ray-emitting BL Lac 4FGL J1219.0+3653 in the Radio. We collect radio data of 4FGL J1219.0+3653, the first γ-ray BL Lac candidate known above redshift 3. We analyze total flux density measurements covering a wide frequency range (0.33–5 GHz) as well as the only available very long baseline interferometry (VLBI) data. The radio spectrum is flat. Based on the radio data, there is no evidence that the compact jet emission is Doppler-enhanced, at odds with the BL Lac classification. The Gaia-VLBI optical-radio positional offset is ~9 mas which appears larger than usual in a blazar-like source but is still within 3σ uncertainties.

Keywords: BL Lacertae objects, Gamma-ray sources, Extragalactic radio sources, Very long baseline interferometry, Active galactic nuclei, Radio continuum emission
SNR 0519‑69.0 as a Type Ia Explosion in a Planetary Nebula Cocoon. The degree to which Type Ia Supernova (SN Ia) progenitors modify their surroundings remains an open question. In this work, we explore the parameter space for circumstellar interaction in Type Ia Supernova Remnant (SNR) 0519‑69.0 by comparing observed archival Chandra spectra with model SNR spectra calculated assuming different SN Ia explosion scenarios and ambient medium (AM) structures. We compared SNR models expanding into a uniform AM with those expanding into a post-common envelope cocoon generated from a planetary nebula model. We conclude that the X-ray spectra and bulk dynamics of SNR 0519‑69.0 are best explained by an interaction with a planetary nebula cocoon, implying that the progenitor of this SN Ia went through a common envelope episode shortly (~10,000 yr) before the SN explosion.

Keywords: Planetary nebulae, Type Ia supernovae, Common envelope evolution
Gas Dynamics in 3 "Dippers": EPIC 203850058, EPIC 204638512, and EPIC 205151387 in 2017–2018. We have examined variability of the three dipper stars—EPIC 203850058, EPIC 204638512, and EPIC 205151387—using the SpeX spectrograph on NASA's Infrared Telescope facility on two nights in 2018. We combined these data with those previously published from 2017. In EPIC 204638512, the He I line was in absorption, but blueshifted in wavelength on all 4 nights, indicating outflowing gas near the disk surface. In EPIC 203850058, no net emission is seen in 2018, but in 2017 it had an absorption core that was degraded to longer wavelengths, suggesting inflowing gas. In EPIC 205151387 the He I line went from emission in the spectrum with the least extinction by dust (highest flux state), became an inverse P Cygni profile, indicating inflowing gas as the extinction increased, and finally to pure absorption when the extinction was greatest.

Keywords: Protoplanetary disks, Circumstellar gas
LOFAR Non-detections of SN 2023ixf in its First Year Post-explosion. We used the LOw Frequency ARray (LOFAR) telescope to monitor SN 2023ixf, a core-collapse supernova in M101, between 8 and 368 days post-explosion. We report non-detections down to ~ 80 μJy sensitivity at 144 MHz. Our non-detections are consistent with published radio observations at higher frequencies. At the time, we are not able to constrain the properties of low-frequency absorption due to the progenitor star's circumstellar medium via these LOFAR observations.

Keywords: Radio continuum emission, Supernovae, Core-collapse supernovae
GHOST Reduced Data Products for the Gemini Observatory Community and Beyond. The Gemini High-resolution Optical SpecTrograph (GHOST) at Gemini South started regular queue operations in early 2024, bringing a long-sought open-access capability to the astronomy community. This research note briefly describes an effort to provide easy-to-access reduced spectra for GHOST programs from all Gemini partner countries and encourage prompt data exploration and analysis. Since 2024 March, over 4500 spectra have been reduced and made available to principal investigators (PIs). The aim is to increase demand for GHOST and expedite the publication of scientific results.

Keywords: High resolution spectroscopy, Astronomy data reduction
HD 193182: A Bright Twin of the Unusual Be-shell Star HD 94509. The star HD 94509 was recognized as an extreme example in the class of Be and shell stars because of its unusual late-type shell spectrum and anomalous line profiles. Using high-resolution and high-signal-to-noise ratio spectroscopy obtained with FIberfed Echelle Spectrograph on Nordic Optical Telescope, we investigate whether HD 193182 is a similarly extreme Be-shell star, as suggested by microphotometer tracings obtained in the 1920s and 1940s. Indeed, both stars turn out to be very similar in terms of photospheric and shell spectra. A basic model atmosphere analysis of HD 193182 is performed using non-LTE line formation calculations.

Keywords: Shell stars, B(e) stars, Spectroscopy
Pre-Outburst Observations of T CRB with a Smart Telescope. T Coronae Borealis is a binary star known as a recurrent nova which has a period of approximately 80 yr whose last two ourtbursts occurred in 1866 and 1946. The American Association Variable Stars Observers in early 2024 launched an observing campaign after a bright state of the star has been observed since 2015, interpreted as a precursor to a new eruption and from the mysterious pre-eruption dip observed since 2023. From 2024 April 2 to November 7, we obtained, through two Seestar S50 smart-telescopes, 8060 unfiltered photometric points. It was thus possible to calculate the orbital period of the binary system found to be 226.1 ± 3.8 days, lower than the officially recognized 227.5687 ± 0.0099 days but within the error bar. No outbursts were observed during this observation period.

Keywords: Recurrent novae, Variable stars, Peculiar variable stars
An Exploration of Molecular Lines for Abundance Analysis in M-dwarf IR Spectra. We identified detectable molecular absorption lines and estimated the abundances of carbon (C), aluminum (Al), chlorine (Cl) and chromium (Cr) in an M dwarf star with Teff ~ 3100 K. We chose a well-studied M-dwarf, HD 125455B, since this star is in a binary pair with K-type star, HD 125455. Abundance analysis was conducted using a high-resolution H-band spectrum from IGRINS. We identified CO lines to test the methodology and identified detectable AlO, HCl, and CrH lines in the IR H-band. We determined upper limits for stellar abundances for [C/H], [Al/H], [Cl/H], and [Cr/H] in HD 125455B and we provided a comparison to known abundances for HD 125455.

Keywords: M dwarf stars, Chemical abundances
V1663 Aquilae: A Fast Fe II-type Nova that Formed Dust and Coronal Lines. V1663 Aquilae was a rare nova that formed both dust and coronal emission lines. A spectrum from 157 days after peak brightness shows both thermal dust emission and coronal emission present at the same epoch. An earlier spectrum from 36 days post maximum captures the nova prior to the formation of either dust or high-excitation emission lines. At the earlier epoch, its emission lines arose mostly from neutral species and singly ionized iron.

Keywords: Novae, Classical novae
Moderate-separation Binary Companions May Influence Young Stellar X-Ray Luminosity. Young pre-main sequence stars exhibit elevated X-ray levels due to their strong magnetic activity. Understanding young stars' X-ray activity is essential for contextualizing the forming planets that they host. Binary stars present a unique environment that may influence planet formation and evolution. In this work, we assembled a sample of 65 systems with stellar characterization from the literature and X-ray fluxes from the XMM-Newton Extended Survey of the Taurus Molecular Cloud to investigate the potential relationship between binary separation and X-ray flux. We found that binary stars with separations smaller than the sample median may exhibit elevated X-ray flux compared to single stars. This suggests that binary companions could influence stellar and planetary evolution and warrants further investigation.

Keywords: X-ray astronomy, Binary stars, Classical T Tauri stars
The Mass–Radius Relation for Planets in Binary Systems. Stellar companion within a few hundred astronomical unit alter the structure and shorten the lifetime of protoplanetary disks, influencing planetary formation and evolution. Such systems host fewer close-in planets, and have fewer ~2.3R⊕ "sub-Neptunes" relative to ~1.3R⊕ "super-Earths" compared to single-star hosts, observations that can be explained by early dissipation of the gas disk. Here we construct the mass–radius diagram of 15 small (&lt;8R⊕), well-characterized planets on S-type orbits in systems with projected separations &lt;500 au, and show that it is indistinguishable from that of planets around single stars. This suggests that accretion of the H2-dominated envelopes of sub-Neptunes could be much faster than gas disk dissipation and limited instead by available solids for cores, or that many sub-Neptunes have envelopes of condensible volatiles such as H2O.

Keywords: Exoplanet atmospheric composition , Binary stars, Exoplanet astronomy, Planet hosting stars, Exoplanet formation, Exoplanet atmospheres
Contamination in Exoplanet Transit Spectroscopy with a Changing Stellar Surface. Inhomogeneities in the stellar surface can lead to differences between the actual and assumed stellar spectrum below the planet's transit chord, causing the inferred planet transmission spectrum to have a contamination component. In this study, we present a simple analytical formula for calculating the contamination spectrum in transmission spectroscopy, taking into consideration the variable spot coverage fraction or spot occultation. We took the temperate sub-Neptune, K2-18 b, as an example to demonstrate the range of the possible contamination spectra under fiducial spot coverage and variability assumptions, which is typically around a few to 15%, which is considerably more than when surface changes were ignored, illustrating the importance of considering these higher-order effects in exoplanet transmission spectroscopic observations.

Keywords: Exoplanets, Transmission spectroscopy, Exoplanet atmospheres, Stellar activity
Comment on "The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study" (2024, AJ, 167, 249) by T. J. Davidge. The paper by T. J. Davidge (2024, AJ, 167, 249) describes experiments to digitize and interpret the digitization of photographic spectra of the bright A0 dwarf Vega using a high-end, flat-bed commercial scanner. While a flat-bed scanner achieves a huge gain in speed compared with what the purpose-built microdensitometer PDS could accomplish, his paper does not offer convincing benefits of the science which methods such as his could produce. This "Comment" explains the important issues that have been identified, and concludes that all is neither as trivial nor as simple as Davidge suggests.

Keywords: Astronomy image processing
A Comparison of Publication Counts for Four Ultraviolet Explorer Observatories. Publication counts for four space-based ultraviolet observatories are compared: International Ultraviolet Explorer (IUE), Extreme Ultraviolet Explorer, Far Ultraviolet Spectroscopic Explorer (FUSE), and Galaxy Evolution Explorer (GALEX). The first three show rapid rises to either a sharp or broad maximum. Over the peak period for IUE the papers tend to be concentrated upon data from that mission specifically. Maxima are followed by declines of various duration, after which papers based upon multiple space-based observatories have lead to extended relevancy for each mission, particularly in the case of FUSE. By contrast, papers that incorporate data from GALEX have yet to evince a turn-over. As with FUSE, there is a pronounced trend for results from the GALEX mission to have been incorporated into multi-mission papers.

Keywords: Ultraviolet observatories
The Double-white-dwarf Merger Rate from ZTF. Using the Zwicky Transient Facility (ZTF), Burdge et al. discovered systems of eclipsing double white dwarfs (EDWDs) having orbital periods &lt; 1 hr. From the properties of 3 of the discovered systems, I estimate a merger rate of DWDs, per unit stellar mass in the Galaxy, of Rmerge,M* ≈ 4.8 × 10‑13 yr . This likely somewhat underestimates the rate, because of several known effects that work against EDWD detection in ZTF. The derived merger rate is within the uncertainty range, Rmerge,M* = (4.6‑5.8) × 10‑13 yr , measured independently by Maoz et al. based on two samples of DWDs discovered via radial-velocity variations. Based on the expected period distribution of DWDs and their detectability, of order 100 additional EDWDs with periods &gt; 1 hr are discoverable in ZTF, with potential to significantly improve the merger-rate's measurement precision.

Keywords: White dwarf stars, Type Ia supernovae
Analysis of Gaia DR3 Data of Selected R Stars (Warm Carbon Stars). An analysis of Gaia DR3 data of 67 R stars is presented and 57 of them are at high galactic latitudes. Three new variable stars are found. The long period luminous variable R stars and R8 stars may be variable carbon stars on the Asymptotic Giant Branch. The R stars seem to have luminosities throughout the Red Giant Branch range. Several R stars are found to be high velocity stars. The determination of s-process elements abundances and C12/C13 ratio of the stars listed in Table 1 will enable us to further understand the R stars phenomenon. The process by which the atmospheres of these stars are enriched with carbon is still a puzzle.

Keywords: R stars
Determination of the Abundance of Mercury from the Hg II Line at 5677.10 Å in Late B-type Stars. XII. HD 7374 (87 Psc). The weak line of Hg II located at 5677.10 Å is not detected in a coadded ELODIE spectrum of the HgMn star HD 7374 which may be explained by the decrease of the signal-to-noise ratio in the red part of the spectrum. The synthesis of various spectral intervals yields several new measurements of the abundances of helium, carbon, oxygen, magnesium, aluminum, silicon, titanium, chromium, manganese, iron, nickel, gallium and yttrium. Most of these new measurements agree well with previous measurements.

Keywords: Mercury-manganese stars, Chemically peculiar stars
Lowell Observatory Near-Earth Object Survey (LONEOS) Bundle V1.0. This bundle contains over 200,000 2.88°x1.44° original and augmented FITS images from the Lowell Observatory Near Earth Objects Survey (LONEOS) using the 0.6m f/1.9 LONEOS Schmidt telescope and the Lowell Observatory Imaging Software (LOIS) versions 3.2.0.beta and 4.2.0 between 2003-08-31 and 2008-03-01. The original images are from Hard Disk Drives (HDDs) obtained from the Lowell Observatory. Numerous dates are missing for a variety of reasons, including no data having been obtained, images obtained but lost, or files too damaged to allow an image to be recovered.

Keywords: Near-Earth objects, Asteroids
Ceres SPC Shape Model and Regional Models of Permanently Shadowed Regions Bundle V1.0. This bundle contains topography and albedo generated for 9 polar craters on asteroid Ceres. Utilizing secondary illumination allows heights to be determined inside Permanently Shadowed Regions (PSRs). A global model is provided for context.

Keywords: Ceres
PRIMASS-L Spectra Bundle V2.0. PRIMASS-L is a spectral library that contains the results of the PRIMitive Asteroids Spectroscopic Survey (PRIMASS). As of the end of 2023 this library contains 438 visible and 264 near-infrared spectra of primitive asteroids from 10 families and two groups that had been sparsely studied before. PRIMASS-L contains spectra from a variety of ground-based facilities.

Keywords: Asteroids
Spacewatch 0.9m Mosaic Camera Survey Bundle V2.0. The Spacewatch 0.9m Mosaic Camera Survey package contains data and documentation covering the survey between 2003 and 2016. The goal of the survey was to discover near-Earth asteroids by observing regions of the sky near the ecliptic and often near opposition. The survey was conducted using the Spacewatch mosaic camera, commissioned in 2002, and the Steward Observatory 0.9m telescope on Kitt Peak in the Tohono O'odham Nation. This update replaced data files with incorrect corner coordinates and added some missing data files.

Keywords: Near-Earth objects, Comets, Asteroids
Arecibo Radar Doppler Spectra of Asteroids V1.0. This bundle contains radar Doppler spectra taken with the Arecibo Observatory Planetary Radar saved as a set of comma-separated-value tables each in a singe file. This version contains the data described in Virkki et al. (2022). See the bundle description for more information.

Keywords: Near-Earth objects, Asteroids
NEAR Magnetometer Bundle V1.0. The NEAR Magnetometer (MAG) is an instrument on the NEAR spacecraft. This bundle contains all of the raw and calibrated MAG instrument data from the NEAR mission, plus derived results.

Keywords: Space probes, Orbiters, Eros, Flyby missions, Solar system astronomy
Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx): Spectral Analysis Bundle V1.0. This bundle collects all the derived spectral data products produced by the OSIRIS-REx Visible and InfraRed Spectrometer (OVIRS) and the OSIRIS-REx Thermal Emission Spectrometer (OTES). These products include resampled and reflectance OVIRS spectra, and temperature/emissivity OTES data products. Additionally, both visible and near infrared (vnir) and thermal infrared (tir) map products are collected.

Keywords: Near-Earth objects, Asteroids