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Forty Hypervelocity Stars from Gaia DR3 Res. Notes AAS Pub Date : 2024-04-24 Mudumba Parthasarathy
Forty hypervelocity stars (HVS) are detected from a search for HVS in Gaia DR3 data whose G magnitudes are less than 17.0 and radial velocities are more +400 km s−1. The Gaia DR3 astrophysical parameters and spectra indicate that most of the HVS reported in this study are F, G, and K type metal-poor stars. Eleven stars are at high galactic latitudes. Included in this study are the B components of six
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Validating Gaia DR3 Pulsating Variable Classifications with TESS: Building Reliable δ Scuti and γ Doradus Stars Catalogs (In Progress)* Res. Notes AAS Pub Date : 2024-04-23 Ai-Ying Zhou
Gaia DR3 revealed 748,058 pulsating variable stars of mixed DSCT∣GDOR∣SXPHE types. This project undertakes a comprehensive examination to validate and distinguish these stars using Transiting Exoplanet Survey Satellite data. Aiming for reliable catalogs of bona fide δ Scuti and γ Doradus stars, I have validated 1715 δ Scuti stars, 1403 γ Doradus stars, and identified 260 eclipsing binaries, one RR
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The FUV Fluxes of A-type Star Members of the Hyades Res. Notes AAS Pub Date : 2024-04-23 Richard Monier
The International Ultraviolet Explorer database has been searched for the FUV spectra of the A stars which are members of the Hyades. Eight out of 16 confirmed members of the Hyades have FUV absolute fluxes obtained with the SWP camera through the large aperture. The observed sharp decrease of the FUV fluxes from spectral type A2 to A9 is essentially a temperature effect. The FUV flux of the A7 IV
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Predicting Stellar Masses of the First Galaxies Using Graph Neural Networks Res. Notes AAS Pub Date : 2024-04-22 Vincent A. Horvath, Snigdaa S. Sethuram and John H. Wise
Theoretical models of galaxy formation and evolution are primarily investigated through cosmological simulations and semi-analytical models. The former method consumes core-hours explicitly modeling the dynamics of the galaxies, whereas the latter method only requires core-hours foregoing directly simulating internal structure for computational efficiency. In this work, we present a proof-of-concept
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ASKAP-EMU Discovery of “Raspberry”: A New Galactic SNR Candidate G308.73+1.38 Res. Notes AAS Pub Date : 2024-04-22 Sanja Lazarević, Miroslav D. Filipović, Bärbel S. Koribalski, Zachary J. Smeaton, Andrew M. Hopkins, Rami Z. E. Alsaberi, Velibor Velović, Brianna D. Ball, Roland Kothes, Denis Leahy and Adriano Ingallinera
We report the Australian Square Kilometre Array Pathfinder discovery of a new Galactic supernova remnant (SNR) candidate G308.73+1.38, which we name Raspberry. This new SNR candidate has an angular size of 20.′7 × 16.′7, and we measure a total integrated flux of 407 ± 50 mJy. We estimate Raspberry’s most likely diameter of 10–30 pc which would place it at a distance 3–5 kpc, in the near side of the
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Hidden Companions to Intermediate-mass Stars. XVIII. Discovery of a 0.88M ⊙, 26 au Companion to n Centauri* Res. Notes AAS Pub Date : 2024-04-22 Idel Waisberg, Ygal Klein and Boaz Katz
n Centauri is a nearby A-type star. Here we report the discovery of a companion with an H band flux ratio at a projected separation ρ = 570 mas ↔ 26 au based on the acquisition camera image of a VLTI/GRAVITY observation. Isochrone fitting yields masses MA = 2.07M⊙ and MB = 0.88M⊙ and an age of 900 Myr. The newly discovered companion explains the Δv = 2.3 ± 0.1 km s−1 Gaia-Hipparcos proper motion change
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The Host Galaxy of a Dormant, Overmassive Black Hole at z = 6.7 may be Restarting Star Formation Res. Notes AAS Pub Date : 2024-04-19 Fabio Pacucci, Abraham Loeb and Ignas Juodžbalis
JWST is discovering a large population of z > 4 supermassive black holes (SMBHs) that are overmassive with respect to the stellar content of their hosts. A previous study developed a physical model to interpret this overmassive population as the result of quasar feedback acting on a compact host galaxy. In this Note, we apply this model to JADES GN 1146115, a dormant SMBH at z = 6.7 whose mass is ∼40%
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Exploring Molecular Gas toward the Magellanic Bridge Res. Notes AAS Pub Date : 2024-04-16 Mariela Celis Peña, Mónica Rubio, Hugo Saldaño, M. T. Valdivia-Mena, Laura Duvidovich and Sergio Paron
The Magellanic Bridge (MB) is a diffuse gas structure that connects the Large Magellanic Cloud with the Small Magellanic Cloud. The MB is the closest tidal interaction system between two galaxies to the Milky Way. Taking into account that young stellar objects are embedded in such gaseous structure, it is a unique laboratory to investigate gas dynamics and star formation processes in a very low metallicity
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Spectral Typing with Artificial Intelligence: Classifying Low-resolution Near-infrared Spectra of Standard M/L/T Dwarfs Res. Notes AAS Pub Date : 2024-04-16 Tianxing Zhou, Christopher A. Theissen, Adam J. Burgasser, William M. J. Best and S. Jean Feeser
We investigate the application of supervised machine learning models to directly infer the spectral types of ultracool dwarfs (dwarf spectral types ≥M6) using binned fluxes as feature labels. We compare the ability of two machine learning frameworks, k-Nearest Neighbor (kNN) and Random Forest (RF), to classify low-resolution near-infrared spectra of M6 to T9 dwarfs (3100 K ≳ Teff ≳ 500 K). We used
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Photometric Analysis of the Nucleus of the Main-belt Comet 2010 LH15 Res. Notes AAS Pub Date : 2024-04-16 M. Mastropietro, H. Krishna, Y. Kim and J. Agarwal
We analyzed the inactive nucleus of the main-belt comet 2010 LH15 at a true anomaly of 262°. Observations using the Gemini North Telescope in 2023 July yielded an absolute R-band magnitude of (18.4 ± 0.2) mag. Assuming a C-type geometric albedo and phase function, we estimated the nucleus radius to be (0.5 ± 0.1) km. The examination of the lightcurve profile did not yield clear evidence for a rotational
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Pipeline Provenance for Analysis, Evaluation, Trust or Reproducibility Res. Notes AAS Pub Date : 2024-04-16 Michael A. C. Johnson, Hans-Rainer Klöckner, Albina Muzafarova, Kristen Lackeos, David J. Champion, Marta Dembska, Sirko Schindler, Marcus Paradies
Data volumes and rates of research infrastructures will continue to increase in the upcoming years and impact how we interact with their final data products. Little of the processed data can be directly investigated and most of it will be automatically processed with as little user interaction as possible. Capturing all necessary information of such processing ensures reproducibility of the final results
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Hidden Companions to Intermediate-mass Stars. XVII. Uncovering a 0.72 M ⊙, 0.35 au Companion in the Spectroscopic Binary Sigma Sculptoris* * Based on observations collected at the European Southern Observatory, Chile, Program ID 109.23BV.001. Res. Notes AAS Pub Date : 2024-04-16 Idel Waisberg, Ygal Klein, Boaz Katz
Sigma Sculptoris is a nearby star that was suspected of being a rotating Ap variable. It was recently found not to be an Ap star but rather a 47 days single-lined spectroscopic binary. Here we report on the direct detection of the companion with a K band flux ratio of 5.5% at a projected separation of 5.16 mas based on a VLTI/GRAVITY observation. We estimate isochrone masses M A = 1.95M ⊙ and M B
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Satellite Visibility During the 2024 April Total Eclipse Res. Notes AAS Pub Date : 2024-04-03 Samantha M. Lawler, Hanno Rein, Aaron C. Boley
On 2024 April 8, tens of millions of people across North America will be able to view a total solar eclipse. Such astronomical events have been important throughout history, but with nearly 10,000 satellites in orbit, we question whether total eclipses will now reveal a sky full of satellites, fundamentally changing this experience for humanity. Using the current population of Starlink satellites,
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A Spectroscopic Characterization of a Blazar Candidate Excluded by Automated Morphology Classification Res. Notes AAS Pub Date : 2024-04-03 Zhang-Liang Xie, Eduardo Bañados, Silvia Belladitta, Chiara Mazzucchelli, Jan-Torge Schindler, Frederick Davies, Bram P. Venemans
Blazars are radio-loud Active Galactic Nuclei (AGNs) with their jets pointing at us at a very small angle. J064334.60–331430.29 (hereafter J0643–3314) was selected as a blazar candidate by its colors and compactness in archival radio images. In Xie et al. 2024, we introduce an algorithm to recognize likely blazars using the morphology observed in the 3 GHz Very Large Array Sky Survey. According to
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The Hybrid Debris Disk Host Star HD 21997 is a High-frequency Delta Scuti Pulsator Res. Notes AAS Pub Date : 2024-04-03 Aldo G. Sepulveda, Timothy R. Bedding, Simon J. Murphy, Luca Matrà, Daniel Huber, Zhoujian Zhang
HD 21997 is host to a prototypical “hybrid” debris disk characterized by debris disk-like dust properties and a CO gas mass comparable to a protoplanetary disk. We use Transiting Exoplanet Survey Satellite time series photometry to demonstrate that HD 21997 is a high-frequency delta Scuti pulsator. If the mode identification can be unambiguously determined in future works, an asteroseismic age of HD 21997
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High Accuracy Photodissociation Rates in VULCAN with MCRT Res. Notes AAS Pub Date : 2024-04-03 Elspeth K. H. Lee, Shang-Min Tsai
Photochemical processing is a key influence on the chemical compositions of exoplanet atmospheres. We develop a 1D plane-parallel Monte Carlo radiative-transfer (MCRT) path length method to calculate actinic fluxes for photochemical modeling, which we couple to the VULCAN photochemical model. Due to the flexible nature of MCRT methods, this enables accurate calculation of photodissociation rates for
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Enhancing Stellar Temperature Estimation through Machine Learning and Multifaceted Data Exploration Res. Notes AAS Pub Date : 2024-04-03 Siddhi Bansal, Phillip Phan, Zayaan Rahman
This paper employs machine learning to estimate stellar temperatures using photometric data, focusing on the GAIA ESA Archive Data Release 3 data set. The study underscores the effectiveness of neural networks in deciphering intricate relationships within the data. Notably, the addition of metallicity improves model accuracy in characterizing stellar properties. The study also investigates outlier
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Intermediate Gas Phases within Turbulent Radiative Mixing Layers Res. Notes AAS Pub Date : 2024-04-03 Meg Georgina Blackburn, Ryan Jeffrey Farber
Turbulent radiative mixing layers (TRMLs) occur ubiquitously in astrophysical environments; e.g., TRMLs are prevalent within galactic outflows at the intersections between hot supernovae ejecta and cold molecular clouds. A velocity shear between the rapidly outflowing hot gas and cold clouds drives the Kelvin–Helmholtz instability producing TRMLs, with radiative cooling dominating the heat transfer
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The Recurrent Nova V745 Sco had a Classical Nova Eruption in 1897 July Res. Notes AAS Pub Date : 2024-03-29 Bradley E. Schaefer
Recurrent nova V745 Sco is discovered to have a long-lost nova eruption in 1897 July. Now with four known eruptions (in 1897, 1937, 1989, and 2014), plus two likely missed eruptions (around 1917 and 1963), the average recurrence time is 23 yr, with a fractional rms of 13%.
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Multi-view Deep Learning for Imaging Atmospheric Cherenkov Telescopes Res. Notes AAS Pub Date : 2024-03-29 Hannes Warnhofer, Samuel T. Spencer, Alison M. W. Mitchell
This research note concerns the application of deep-learning-based multi-view-imaging techniques to data from the High Energy Stereoscopic System Imaging Atmospheric Cherenkov Telescope array. We find that the earlier the fusion of layer information from different views takes place in the neural network, the better our model performs with this data. Our analysis shows that the point in the network
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On the Plasma Quasi-thermal Noise in the Outer Heliosphere Res. Notes AAS Pub Date : 2024-03-29 Nicole Meyer-Vernet, Alain Lecacheux
The recent paper by Li et al. on electron quasi-thermal noise (QTN) in the outer heliosphere is flawed. It assumes the plasma drift speed to be much smaller than the electron thermal speed, even though both quantities are of the same order of magnitude in the outer heliosphere inward of the termination shock, because of the low plasma temperature. In this case, the Langmuir wave dispersion equation
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Extinction along Sightlines Sampled by the APO Catalog of DIBs Res. Notes AAS Pub Date : 2024-03-28 Helena Xing, Ailish Sullivan, Halis Seuret, Cercis Morera-Boado, Tina A. Harriott, Daniel Majaess, Lou Massa, Chérif F. Matta
Identification of molecular carriers for diffuse interstellar bands (DIBs) may stem in part from the determination of interrelated lines using the Apache Point Observatory Catalog of DIBs. However, Pearson correlations may be impacted by the number of interstellar clouds along the sightlines. The trend of extinction with distance was constrained using Bayestar19 and Gaia DR3, and clouds were identified
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A Possible Cyclotron Feature of the Gamma-Ray Binary 4FGL J1405.1–6119 Res. Notes AAS Pub Date : 2024-03-28 Sung-Chieh Chiu, Kwan-Lok Li
We reanalyzed the X-ray observations of the γ-ray binary candidate 4FGL J1405.1−6119 using the XMM-Newton observations. In the X-ray spectra, we find a weak absorption feature around 2 keV in the XMM-Newton observations, which could be the cyclotron resonant scattering feature (CRSF) or so called cyclotron line of the possible neutron star (NS) in the binary. The line energy of the CRSF is ∼2 keV,
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Anthropogenic Coal Ash as a Contaminant in an Underwater Search. II. Beyond Beryllium, Lanthanum, and Uranium Res. Notes AAS Pub Date : 2024-03-21 Patricio A. Gallardo
It has been shown that the Beryllium, Lanthanum and Uranium concentrations in the “BeLaU” spherules are in the expected ranges of coal ash. It is reported that the average elemental concentration of 12 microspherules can be found in the COALQUAL database in 98% (49/50) of the elements examined. The “BeLaU pattern” is found to be not unique, it can be reproduced using a coal ash standard (SRM1633a)
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HST Far-ultraviolet Transit Observations of Two Neptune Progenitors Younger than 30 Myr Res. Notes AAS Pub Date : 2024-03-21 Adina D. Feinstein, Kevin France, P. Wilson Cauley, John H. Livingston
Photoevaporation is believed to dominate the removal of planetary atmospheres when they are young (<100 Myr). Signatures of atmospheric mass-loss can be observed in the ultraviolet (UV) through the near-infrared. We present Far-UV transit observations of AU Mic b (∼22 Myr) and V1298 Tau c (∼28 Myr) with the Hubble Space Telescope. We search for evidence of escaping metals in the C ii, Si ii, and Si iii
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Polarimetry of GRB 230818A Res. Notes AAS Pub Date : 2024-03-21 Denis Bernardes, Iain Steele, Helen Jermak, Callum McCall
We present a preliminary analysis of optical photometric and polarimetric observations of GRB 230818A obtained with the Liverpool Telescope starting 3.2 minutes after the alert. The optical photometry suggests a reverse shock-dominated afterglow, transitioning to forward shock at around 15 minutes. The polarization shows a low degree (upper limit 6%) early in the light curve. This is in contrast to
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The Selection Function of Gaia DR3 RR Lyrae Res. Notes AAS Pub Date : 2024-03-20 Cecilia Mateu
The Third Data Release (DR3) of the Gaia mission almost doubled the number of RR Lyrae (RRL) stars release in its Specific Object Studies (SOS) catalog, in comparison with DR2. Here I provide empirically inferred 2D and 3D completeness maps for the Gaia DR3 SOS RRL catalog along with maps for the combined Gaia SOS+PS1+ASAS-SN-II catalog. The latter currently has the best performance with an improvement
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Machine Learning-based Classification of Variable Stars Res. Notes AAS Pub Date : 2024-03-19 Anjie Liu, Jasmine C. Xu
The classification of variable stars, essential for revealing information on stellar properties and cosmic distances, traditionally relied on statistical methods and limited data. With the emergence of transformative machine learning methodologies and large stellar surveys, we are able to perform more efficient, accurate, and robust handling of expansive databases. We deploy two different machine learning
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Lopsided Galaxy Distributions in Massive TNG300 Clusters Res. Notes AAS Pub Date : 2024-03-19 Kelsey A. Mangis, Tereasa G. Brainerd
Studies of isolated central galaxies and their satellites have shown that the spatial distributions of the satellites are distinctly “lopsided” with respect to the locations of the central galaxies. Here we extend this type of analysis to larger systems by analyzing the lopsidedness of 280 massive galaxy clusters in the IllustrisTNG300 Λ Cold Dark Matter simulation. Using a pairwise clustering statistic
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Classifying Emission-line Galaxies Using a Dense Neural Network and Support Vector Machine Res. Notes AAS Pub Date : 2024-03-18 Ayan Gupta, Jazhiel Segura-Monroy, Yash Totlani
In this study we present an innovative approach to classifying emission-line galaxies, specifically categorizing them as Star-forming, Seyfert, Low Ionization Nuclear Emission Line Regions, or Composites. Leveraging both a Dense Neural Network and Support Vector Machine, we use key emission-line flux ratios as input features extracted from the Baryon Oscillation Spectroscopic Survey data within the
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A Selection of 23 Bright Hypervelocity Gaia DR3 Stars Res. Notes AAS Pub Date : 2024-03-15 Mudumba Parthasarathy
From the Gaia DR3 data twenty three bright hypervelocity stars that have Tycho catalogue numbers are presented. All these stars are of high galactic latitude and some may be galactic halo stars. All of them have accurate Gaia DR3 parallaxes and radial velocities. There is hardly any relevant literature on some of these stars. The Gaia DR3 astrophysical parameters of some of these stars indicate that
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Variability Census of Legacy Catalogs. II. 6600+ New δ Scuti and γ Doradus Stars* * Dedicated to my wife Jingyun Zhang. Res. Notes AAS Pub Date : 2024-03-15 Ai-Ying Zhou
From Phase II of a variability vetting census in BD, HD, SAO and PPM catalogs, I have identified a total of new variables of over 5000 δ Scuti, 3500 γ Doradus, 1200 Maia variables, 4 RR Lyrae stars, 420 eclipsing binaries, 5500 rotating variables (220+ ellipsoidal variable stars, 550+ ACV and several other subtypes including solar-like oscillators), and other types. Notably, more than 66 eclipsing
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CO and C i Emission in the Early Spectrum of the Nova V1391 Cassiopeiae Res. Notes AAS Pub Date : 2024-03-15 Richard J. Rudy, Ray W. Russell, Michael L. Sitko, Hideyo Kawakita
V1391 Cassiopeiae is one of a growing number of novae to show emission from carbon monoxide but only the second to display molecular absorption as well (after V2676 Ophiuchi). In this Research Note, we present a 0.69–5.2 μm spectrum that includes both the CO fundamental and first overtone as well as a prominent, very low ionization spectrum dominated by the lines of C i. Relative to the CO first overtone
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Lightcurve Analysis of a Sample of Asteroids and Comets Observed with the Isaac Newton Telescope Res. Notes AAS Pub Date : 2024-03-14 Isaac J. B. Holst, James Robinson, Abbie Donaldson
We present an analysis of six asteroids and one comet using data from the Wide Field Camera on the Isaac Newton Telescope, La Palma. As part of this work we developed a pipeline to reduce and absolutely calibrate photometry of inactive small bodies. For three of the objects, there was sufficient data to measure their rotation periods. We report rotation periods of (2.7774 ± 0.0004) hr and (3.121 ± 0
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A Catalog of Compact Blue Strongly Lensed Sources in the Footprint of Ground-based Surveys Res. Notes AAS Pub Date : 2024-03-14 Nicola R. Napolitano, Yue Dong, Rui Li
We present a catalog of Compact Blue Strongly Lensed Sources in the footprint of ground-based surveys. We visually inspected the high-quality strong lensing candidates from the Kilo Degree Survey, the Hyper Suprime-Cam Subaru Strategic Program and the Dark Energy Survey. We have collected 63 multiple-imaged systems that are similar to the lensed post-blue nuggets found in Napolitano et al. and fully
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Neglect of Small Spots Remains an Explanation of the Difference Between SOON and RGO Spot Areas Res. Notes AAS Pub Date : 2024-03-14 Peter Foukal
I point out that the objection of Györi et al. to my finding that neglect of small spots could explain much of the puzzling difference between Royal Greenwich Observatory and Solar Optical Observation Network spot areas is not valid because their analysis was limited to only 1974–76, when activity was low. The 40%–50% difference occurs only at higher activity levels.
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A Spectroscopic Hunt for Post-red Supergiants in the Large Magellanic Cloud. I. Preliminary Results Res. Notes AAS Pub Date : 2024-03-13 Kaitlyn M. Chen, Trevor Z. Dorn-Wallenstein
Yellow supergiants (YSGs) are rare and poorly understood, and studying them is critical to constraining massive star evolution. We obtained flux-calibrated Magellan Inamori Kyocera Echelle high-resolution spectra of 40 YSGs in the Large Magellanic Cloud (LMC); this sample likely contains post-red supergiants. Fitting these data with ATLAS9 model atmospheres, we determined fundamental parameters for
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Multiwavelength Catalog of 10,000 4XMM-DR13 Sources with Known Classifications Res. Notes AAS Pub Date : 2024-03-13 Yichao Lin, Hui Yang, Jeremy Hare, Igor Volkov, Oleg Kargaltsev
We present a collection of ∼10,000 X-ray sources from the 4th XMM-Newton Serendipitous Source Catalog (4XMM-DR13) with literature-verified classifications and multi-wavelength (MW) counterparts. We describe the process by which MW properties are obtained and an interactive online visualization tool we developed.
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Massive OB Star Clusters in Cassiopeia Res. Notes AAS Pub Date : 2024-03-12 Kate Saltovets, M. Virginia McSwain
We present a new investigation of several sparse OB associations in Cassiopeia (Cas OB2, OB4, OB5, OB7, and OB8) to revisit their membership and kinematics in the Gaia era. We compare the spatial distribution of the OB associations’ members, the known OB-type stars from the Reed catalog, and candidate hot stars from the Gaia Data Release 3. We also investigate the reddening distributions across the
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Uncertainty Estimation in Exoplanet System Parameters Res. Notes AAS Pub Date : 2024-03-12 Shruti Subramaniyan, Harsh Mehta, Mark R. Swain, Geoffrey Bryden, Matthew Salinas
The NASA Exoplanet Archive contains published data for various stellar and planetary parameters, based on the combined work of hundreds of research teams. For cases where a parameter has been estimated multiple times, the opportunity exists to compare the variance in an estimated parameter value with the reported uncertainties. This study focuses on eleven system parameters that are needed for interpreting
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Characterization of Instrumental Polarization in the MOPTOP Instrument Res. Notes AAS Pub Date : 2024-03-12 Denis Bernardes, Iain Steele, Helen Jermak, Callum McCall
MOPTOP is a polarimeter currently installed on the fully robotic 2 m Liverpool Telescope, designed to allow accurate measurements of the variability of the polarization of astronomical objects like gamma-ray bursts and blazars. In this work, we present the characterization of the field position dependent instrumental polarization added by MOPTOP to the acquired images. This characterization is done
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The Abundances of the Noble Gases Neon and Xenon in the Atmosphere of 53 Tau (HD 27295) Res. Notes AAS Pub Date : 2024-03-12 Richard Monier
One line of Ne i and three lines of Xe ii are synthesized in order to derive the abundances of neon and xenon in the atmosphere of the Mn-rich star 53 Tau. Neon is clearly very underabundant in 53 Tau, its abundance must be lower than 10−3 times the solar neon abundance. Xenon is found to be overabundant with a factor of 3000 times the solar abundance which agrees well with earlier measurements. The
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The Expertise Finder: Using NASA ADS for Panel Reviewer Selection Res. Notes AAS Pub Date : 2024-03-11 Máire Volz, Isabelle Hoare, Kaniyah Harris, Mallory Helfenbein, Antonino Cucchiara
Astronomical research is often made possible by the utilization of different resources that support members of the community in their research endeavors (e.g., telescopes access, or funds). Often, the entities that provide these resources establish a competitive process, which include the submission, by interested parties, of research proposals describing the research objectives and how the resources
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A Constrained Dust Opacity for Models of Dense Clouds and Protostellar Envelopes Res. Notes AAS Pub Date : 2024-03-07 Klaus M. Pontoppidan, Neal Evans, Jennifer Bergner, Yao-Lun Yang
Radiative transfer models of dense clouds and protostellar envelopes rely on the availability of appropriate dust opacities, particularly as new JWST data become available. We present the model opacity known as KP5, which fits the (1–1000 μm) extinction curve measured for icy dust in dense molecular clouds by Spitzer and JCMT, and has been used by the community since 2009, but not previously published
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Modeling the Light Curve of HD 222925's Progenitor Kilonova Res. Notes AAS Pub Date : 2024-03-05 Ian P. A. Johnson, Erika M. Holmbeck
The leading theory for heavy element nucleosynthesis is that a majority of isotopes heavier than iron are formed in neutron star mergers (NSMs), visible through the kilonovae that proceed them. In this work, we derive the potential kilonova light curve associated with the elemental abundances of the “gold standard” metal-poor star HD 222925, which is thought to be enriched by a single NSM. Previous
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A Possible Extremely Fast Spinning White Dwarf in the Intermediate Polar SDSS J0932+47 Res. Notes AAS Pub Date : 2024-03-05 Jordan Tweddale, Peter Garnavich, Mark R. Kennedy
We analyze the far-ultraviolet light curve of the intermediate polar (IP) candidate SDSS-J093249.57+472523.0 (J0932+47), as observed by Hubble Space Telescope/Cosmic Origins Spectrograph. The power spectrum displays two periodicities at frequencies of 2.01 and 0.462 cycles minute−1, corresponding to periods of 29.8 and 130 s. We estimate the significance of the 29.8 s peak to be 3σ. The detection of
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A Radio Galaxy Gravitational Lens in the COSMOS-Web Survey Res. Notes AAS Pub Date : 2024-03-05 Charlotte Moore, Mark Lacy
COSMOS 5914+1219 is a radio galaxy that is gravitationally lensing a background star-forming galaxy. We use a total of eight Hubble Space Telescope and JWST images to model the radio source host galaxy as a bulge plus disk system and fit the photometry from the optical through mid-infrared. We find best-fitting photometric redshifts of ≈1.65 for the radio galaxy and ≈4 for the lensed galaxy. We confirm
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Negative Cosmic Evolution of BL Lac Objects from the Sloan Digital Sky Survey Res. Notes AAS Pub Date : 2024-03-05 Octavia D. Clapp, Richard M. Plotkin, Scott F. Anderson
BL Lacertae (BL Lac) objects are a type of active galactic nucleus (AGN) characterized by featureless optical spectra, where a relativistic jet is oriented toward the observer. By studying BL Lacs objects, we improve our understanding of accretion processes, high-energy particle acceleration, magnetic field structures in extreme environments, and galaxy formation and evolution. Generally, luminous
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Inferences Regarding a Stellar Metallicity Distribution Following a Single Primordial Chemical Enrichment Event Res. Notes AAS Pub Date : 2024-03-05 Graeme H. Smith
An idealized scenario is presented according to which a power-law distribution in metallicity might have characterized the first metal-poor stars. The scenario assumes an initial synthesis of heavy elements within a first source of metals, followed by a subsequent ejection of these metals and their dilution within a metal-free gas environment.
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The Infrared Variability of V1647 Ori over 26 yr with Spitzer, (NEO)WISE, and ISO Res. Notes AAS Pub Date : 2024-03-05 Chinmay S. Kulkarni, Thomas Behling, Nathanael Burns-Watson, Jason Jones, Tyler Robbins, S. Thomas Megeath, Samuel Federman, William J. Fischer, Robert Gutermuth, Riwaj Pokhrel, Wafa Zakri, Savio B. Oliveira
Outbursts from young Class 0 protostars are now being detected using 3–5 μm light curves assembled from Spitzer and WISE/NEOWISE photometry. For comparison, we present a 4–8 μm light curve of the erupting, more evolved protostar V1647 Ori (HOPS 388), assembled from photometry obtained with the ISOCAM camera on ISO, the IRAC camera on Spitzer, and from WISE and NEOWISE. Covering 26 yr, this light curve
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Quasars versus Microquasars: Scaling and Particle Acceleration Res. Notes AAS Pub Date : 2024-03-05 J. I. Katz
Quasars and microquasars both contain accreting black holes and power nonthermal double radio sources, but differ in more than their scales: Quasars are proportionally much more efficient accelerators of energetic electrons. The radio luminosity of the double radio sources associated with quasars, reflecting the long-time average of the particle acceleration power, is often 1%–30% of the quasar’s bolometric
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On Boundary Conditions for Magnetohydrodynamic Waves in Flux Tubes with a Pressure Jump Res. Notes AAS Pub Date : 2024-03-05 Hans Goedbloed, Stefaan Poedts
It is proved that the recent paper by Yelagandula on “a new insight” on the boundary conditions to be applied to magnetohydrodynamic waves in magnetic flux tubes with a finite thermal pressure jump at the boundary is fundamentally wrong. It exploits the wrong variables and assumes a fixed instead of a moving boundary.
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The Far Ultraviolet Light Curve of 78 Vir (A2p SrCrEu) Res. Notes AAS Pub Date : 2024-03-04 Richard Monier
All IUE spectra obtained shortwards of 2000 Å with the SWP camera are used to construct a far-ultraviolet (FUV) light curve at 1500 Å for 78 Vir over its rotational period. Setting an arbitrary phase 0.00 for the first spectrum recorded on 1987 May 10, the minimum and maximum occur respectively near phases 0.20–0.25 and 0.60–0.70. The Fine Error Sensor counts, which measure the brightness near the
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Galactic Archeology with Luminous Red Giant Oscillations in Gaia DR3 Photometry Res. Notes AAS Pub Date : 2024-03-04 Bryan Nnadi, Samuel Grunblatt
Asteroseismology has significantly advanced the field of Galactic archeology, providing essential insights into the formation and evolution of our Galaxy. Here we present an asteroseismic analysis of 103 luminous red giant stars that were observed by Gaia in our Galaxy and the Large Magellanic Cloud. Leveraging a period–luminosity–amplitude relationship determined using data from the OGLE mission,
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Hidden Companions to Intermediate-mass Stars. XVI. Unveiling a 41,300 au Companion to the Very Eccentric Binary Zeta Boötis Res. Notes AAS Pub Date : 2024-03-01 Idel Waisberg, Ygal Klein, Boaz Katz
Zeta Boötis is a nearby 2.2 M ⊙ + 2.2 M ⊙ 125 yr period visual binary distinguished by its very high eccentricity e ≈ 0.98. Here we report that HIP 71759 is a very wide 1.65 M ⊙ companion to ζ Boo at a projected separation ρ=13.′3↔41,300au , an association that has been missed in previous wide binary searches. We estimate a projected velocity difference Δv 2D = 0.86 ± 0.20 km s−1 compared to the Newtonian
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A Possible Meteoric Fall in Cabeza la Vaca (Spain) in 1970 January Res. Notes AAS Pub Date : 2024-03-01 J. M. Vaquero, C. Sánchez Romero, L. Díaz-Condiño, M. C. Gallego
We recover a report in the “HOY” regional newspaper about a presumed meteorite fall near Cabeza la Vaca, Spain. The report details observable effects like a crater, uprooted tree, and a destroyed fence. While the exact date is unknown, it likely occurred within a week of 1970 January 27. The report lacks the crater size specification. This research note underscores the potential significance of the
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Imaging Spectropolarimetry—A New Observing Mode on the Hubble Space Telescope’s Advanced Camera for Surveys Res. Notes AAS Pub Date : 2024-03-01 Nimish P. Hathi, Dean C. Hines, Yotam Cohen, Norman A. Grogin, Marco Chiaberge
Imaging spectropolarimetry is a new observing mode on the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope (HST) that was commissioned in Cycle 30 and is available to HST observers starting in Cycle 31 (i.e., from 2023). It is a technique that is accessible from ground-based observatories, but the superb spatial resolution afforded by HST/ACS combined with the slitless nature of
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Scientific Impact of Novel Instrumentation: The Case of MUSE Res. Notes AAS Pub Date : 2024-03-01 Martin M. Roth
In the process of transforming science cases into a viable and affordable design for a novel instrument, there is the problem of how to gauge their scientific impact, especially when they end up in competing top level requirements that can be incompatible with each other. This research note presents a case study for scientific impact of the integral field spectrograph MUSE in terms of number of refereed
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TOI-6883.01: A Single-transit Planet Candidate Detected from TESS Res. Notes AAS Pub Date : 2024-02-26 G. Conzo, M. Moriconi
A new candidate exoplanet, proposed in ExoFOP by authors, it was promoted from TIC 393818343 to TOI-6883.01 at coordinates R.A.(J2000)20:41:10.01 decl.(J2000) + 3:38:17.87 in the Delphinus constellation and its distance is (93.73 ± 0.35) pc from Earth. The target star is a Sun-type having G0 class according to Skiff spectral classification and it has photometric magnitude V(Johnson) = 9.5 mag. We analyzed
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AI-enhanced Citizen Science Discovery of an Active Asteroid: (410590) 2008 GB140 Res. Notes AAS Pub Date : 2024-02-23 Colin Orion Chandler, Nima Sedaghat, William J. Oldroyd, Chadwick A. Trujillo, William A. Burris, Henry H. Hsieh, Jay K. Kueny, Kennedy A. Farrell, Jarod A. DeSpain, Mark Jesus Mendoza Magbanua, Scott S. Sheppard, Michele T. Mazzucato, Milton K. D. Bosch, Tiffany Shaw-Diaz, Virgilio Gonano, Al Lamperti, José A. da Silva Campos, Brian L. Goodwin, Ivan A. Terentev, Charles J. A. Dukes
We report the discovery of cometary activity emanating from Main-belt asteroid 410590 (2008 GB140), a finding facilitated, for the first time, by an artificial intelligence (AI) assistant. The assistant, TailNet, is a prototype we designed to enhance volunteer efforts of our Citizen Science project Active Asteroids, a NASA Partner program hosted on the Zooniverse platform. Our follow-up investigation