Sazuna/UAT_keywords huggingface dataset:
KIC 9028474: A Long-period Eclipsing Binary on a Highly Eccentric Orbit. We present a comprehensive analysis of a very long-period (124.93669 days) eclipsing binary KIC 9028474, which is composed of F9V+G1V components on a highly eccentric (e = 0.82029) orbit. Masses and radii of the primary and the secondary components are M 1 = 1.18 ± 0.04 M ⊙, M 2 = 1.04 ± 0.03 M ⊙, R 1 = 1.52 ± 0.02 R ⊙, and R 2 = 1.11 ± 0.01 R ⊙, respectively. Eclipse time variations show the presence of apsidal motion, which in turn shows the existence of a third body in a relatively close orbit. Simultaneous analysis of infrared spectra and space photometry reveals that the primary component is about to leave the main sequence, indicating an age of 5.2 ± 0.8 Gyr for the system. Theoretical evaluation of the observed eccentricity indicates that the components of KIC 9028474 will end their whole life much before the orbital circularization is achieved. Given the limited resolution of the spectra, we can only place an upper limit on the rotational velocities of each star, thus a theoretical evaluation of the synchronization of the components.

Keywords: Eclipsing binary stars, Eccentricity, Fundamental parameters of stars, Detached binary stars
A Rotating Accretion Disk around MWC 297, a Young B1.5Ve Star. High-resolution spectra with iSHELL on IRTF in the K and M bands of the young, heavily accreting B1.5Ve star MWC 297 show numerous double-peaked CO lines. These CO lines originate in an inclined gaseous disk in Keplerian rotation. MWC 297 is the only early B star known to show a Keplerian disk in CO. Analysis of the spectra shows that 12CO 1-0 is optically thick for the low excitation lines. Even the 13CO 1-0 and 12CO 2-1 have somewhat optically thick lines at low J levels. We find that the CO emission in the disk can be fitted with CO being in a narrow ring at a radius of 12 au, with a temperature of 1500 K and a CO column density of 1.6 × 1018 cm-2. This model underestimates the line strength of high-J lines, indicating that they are excited by fluorescence. The CO overtone lines have a similar temperature. The 13CO lines are much brighter than expected from interstellar isotope ratios. The 13CO lines are wider than the 12CO ones, suggesting different excitation conditions. The same is true for 12CO 2-1. We see strong absorption in 12CO and 13CO 1-0 at low J levels, which is due to two cold foreground clouds. These clouds, one with a temperature of 8.3 K and a column density of 6.7 1017 cm-2 and the other one colder and with lower column density, can fully account for the observed extinction toward MWC 297.

Keywords: Massive stars, Star forming regions, Far infrared astronomy, Star formation, Circumstellar disks
SOLES. VII. The Spin-Orbit Alignment of WASP-106 b, a Warm Jupiter along the Kraft Break. Although close-orbiting, massive exoplanets-known as hot and warm Jupiters-are among the most observationally accessible known planets, their formation pathways are still not universally agreed upon. One method to constrain the possible dynamical histories of such planets is to measure the systems' sky-projected spin-orbit angles using the Rossiter-McLaughlin effect. By demonstrating whether planets orbit around the stellar equator or on offset orbits, Rossiter-McLaughlin observations offer clues as to whether the planet had a quiescent or violent formation history. Such measurements are, however, only a reliable window into the history of the system if the planet in question orbits sufficiently far from its host star; otherwise, tidal interactions with the host star can erase evidence of past dynamical upheavals. We present a WIYN/NEID Rossiter-McLaughlin measurement of the tidally detached ( ${\boldsymbol{a}}/{R}_{* }={13.18}_{-0.37}^{+0.35}$ ) warm Jupiter WASP-106 b, which orbits a star along the Kraft break (T eff = 6002 ± 164 K). We find that WASP-106 b is consistent with a low spin-orbit angle ( $\lambda ={6}_{-16}^{+17}\,^\circ $ and $\psi ={26}_{-17}^{+12}\,^\circ $ ), suggesting a relatively quiescent formation history for the system. We conclude by comparing the stellar obliquities of hot and warm Jupiter systems, with the WASP-106 system included, to gain insight into the possible formation routes of these populations of exoplanets.

Keywords: Exoplanet dynamics, Planetary theory, Exoplanets, Planetary alignment, Exoplanet systems, Star-planet interactions
Detecting New Visual Binaries in Gaia DR3 with Gaia and Two Micron All Sky Survey (2MASS) Photometry. I. New Candidate Binaries within 200 pc of the Sun. We present a method to identify likely visual binaries in Gaia eDR3 that does not rely on parallax or proper motion. This method utilizes the various point-spread function sizes of Two Micron All Sky Survey (2MASS)/Gaia, where at &lt;2.″5 two stars may be unresolved in 2MASS but resolved by Gaia. Due to this, if close neighbors listed in Gaia are a resolved pair, the associated 2MASS source will have a predictable excess in the J band that depends on the ΔG of the pair. We demonstrate that the expected relationship between 2MASS excess and ΔG differs for chance alignments, as compared to true binary systems, when parameters like magnitude and location on the sky are also considered. Using these multidimensional distributions, we compute the likelihood of a close pair of stars to be a chance alignment, resulting in a total(clean) catalog of 68,725(50,230) likely binaries within 200 pc with a completeness rate of ~75%(~64%) and contamination rate of ~14%(~0.4%). Within this, we find 590 previously unidentified binaries from Gaia eDR3 with projected physical separations &lt;30 au, where 138 systems were previously identified, and for s &lt; 10 au we find that 4 out of 15 new likely binaries have not yet been observed with high-resolution imaging. We also demonstrate the potential of our catalog to determine physical separation distributions and binary fraction estimates, from this increase in low-separation binaries. Overall, this catalog provides a good complement for the study of local binary populations by probing smaller physical separations and mass ratios, and provides prime targets for speckle monitoring.

Keywords: Close binary stars, Visual binary stars, Catalogs
Understanding the Planetary Formation and Evolution in Star Clusters (UPiC). I. Evidence of Hot Giant Exoplanets Formation Timescales. Planets in young star clusters could shed light on planet formation and evolution since star clusters can provide accurate age estimation. However, the number of transiting planets detected in clusters was only ~30, too small for statistical analysis. Thanks to the unprecedented high-precision astrometric data provided by Gaia DR2 and Gaia DR3, many new open clusters (OCs) and comoving groups have been identified. The Understanding Planetary Formation and Evolution in Star Clusters project aims to find observational evidence and interpret how planets form and evolve in cluster environments. In this work, we cross match the stellar catalogs of new OCs and comoving groups with confirmed planets and candidates. We carefully remove false positives and obtain the biggest catalog of planets in star clusters up to now, which consists of 73 confirmed planets and 84 planet candidates. After age validation, we obtain the radius-age diagram of these planets/candidates. We find an increment in the fraction of hot Jupiters (HJs) around 100 Myr and attribute the increment to the flyby-induced high-e migration in star clusters. An additional small bump of the fraction of HJs after 1 Gyr is detected, which indicates the formation timescale of HJ around field stars is much larger than that in star clusters. Thus, stellar environments play important roles in the formation of HJs. The hot Neptune desert occurs around 100 Myr in our sample. A combination of photoevaporation and high-e migration may sculpt the hot Neptune desert in clusters.

Keywords: Exoplanet catalogs, Exoplanets, Astrostatistics, Exoplanet evolution, Open star clusters
UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light. The proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. However, the complex scattered-light structures in the AB Aur disk pose challenges in resolving the emission source and interpreting the true nature of AB Aur b. We present new images of the AB Aur system obtained using the Hubble Space Telescope Wide Field Camera 3 in the ultraviolet (UV) and optical bands. AB Aur b and the known disk spirals are recovered in the F336W, F410M, and F645N bands. The spectral energy distribution of AB Aur b shows absorption in the Balmer jump, mimicking that of early-type stars. By comparing the colors of AB Aur b to those of the host star, the disk spirals, and predictions from scattered light and self-luminous models, we find that the emission from AB Aur b is inconsistent with planetary photospheric or accretion shock models. Instead, it is consistent with those measured in the circumstellar disks that trace scattered light. We conclude that the UV and visible emission from AB Aur b does not necessitate the presence of a protoplanet. We synthesize observational constraints on AB Aur b and discuss inconsistent interpretations among different data sets. Considering the significance of the AB Aur b discovery, we advocate for further observational evidence to verify its planetary nature.

Keywords: Exoplanets, Hubble Space Telescope, Ultraviolet color, HST photometry, Direct imaging, Protoplanetary disks
A Crater Chronology for the Jupiter's Trojan Asteroids. We present a new crater chronology for Jupiter's Trojan asteroids. This tool can be used to interpret the collisional history of the bodies observed by NASA's Lucy mission. The Lucy mission will visit a total of six Trojan asteroids: Eurybates, Polymele, Orus, Leucus, and the near-equal-mass binary Patroclus-Menoetius. In addition, Eurybates and Polymele each have a small satellite. Here we present a prediction of Trojan cratering based on current models of how the solar system and the objects themselves evolved. We give particular emphasis to the time lapsed since their implantation into stable regions near Jupiter's Lagrangian L4 and L5 points. We find that cratering on Trojans is generally dominated by mutual collisions, with the exception of a short period of time (~10 Myr) after implantation, in which cometary impacts may have been significant. For adopted crater scaling laws, we find that the overall spatial density of craters on Trojans is significantly lower than that of Main Belt asteroids on surfaces with similar formation ages. We also discuss specific predictions for similar-sized Eurybates and Orus, and the binary system Patroclus-Menoetius.

Keywords: Jupiter trojans
Extended Habitability of Exoplanets Due to Subglacial Water. Considering subglacial liquid water, a significant extension of the classical Habitable Zone is obtained. Elaborating on the model of Wandel it is shown how an atmosphere and liquid water could survive on tidally locked planets closely orbiting an M-dwarf host, extending the Habitable Zone boundary inwards. In addition, subglacial liquid water could extend the Habitable Zone beyond the outer boundary of the conservative Habitable Zone as well. These two results enhance the circumstellar region with a potential for liquid water well beyond the conservative boundaries of the classical Habitable Zone. It is argued that the probable recent JWST detection of atmospheric water vapor on the rocky Earth-sized exoplanet GJ 486 b, along with earlier detections of water on other planets orbiting M-dwarf stars, gives an empirical answer to the much-argued question of whether such planets can support liquid water, organic chemistry, and eventually life. It is shown how water on terrestrial planets closely orbiting M-dwarf stars may sustain in a subglacial melting layer. Finally, the model is applied to a few exoplanets demonstrating how water detection may constrain their atmospheric properties.

Keywords: Extrasolar rocky planets, M dwarf stars, Exoplanets, Greenhouse effect, Super Earths, Planetary climates, Habitable zone, Habitable planets, Exoplanet atmospheres
Revisiting the Transit Timing and Atmosphere Characterization of the Neptune-mass Planet HAT-P-26 b. We present a transit-timing variation (TTV) and planetary atmosphere analysis of the Neptune-mass planet HAT-P-26 b. We present a new set of 13 transit light curves from optical ground-based observations and combine them with light curves from the Wide Field Camera 3 on the Hubble Space Telescope, the Transiting Exoplanet Survey Satellite, and previously published ground-based data. We refine the planetary parameters of HAT-P-26 b and undertake a TTV analysis using 33 transits obtained over seven years. The TTV analysis shows an amplitude signal of 1.98 ± 0.05 minutes, which could result from the presence of an additional ~0.02 M Jup planet at a 1:2 mean-motion resonance orbit. Using a combination of transit depths spanning optical to near-infrared wavelengths, we find that the atmosphere of HAT-P-26 b contains ${2.4}_{-1.6}^{+2.9}$ % H2O with a derived temperature of ${590}_{-50}^{+60}$ K.

Keywords: Exoplanet astronomy, Timing variation methods, Exoplanet atmospheres
Astrophysical Distance Scale. VII. A Self-consistent, Multiwavelength Calibration of the Slopes and Relative Zero Points for the Run of Luminosity with the Color of Stars Defining the Tip of the Red Giant Branch. Given the recent successful launch of the James Webb Space Telescope, determining robust calibrations of the slopes and absolute magnitudes of the near- to mid-infrared tip of the red-giant branch (TRGB) will be essential to measuring precise extragalactic distances via this method. Using ground-based data of the Large Magellanic Cloud from the Magellanic Clouds Photometric Survey along with near-infrared (NIR) data from 2MASS and mid-infrared (MIR) data collected as a part of the SAGE survey using the Spitzer Space Telescope, we present slopes and zero-points for the TRGB in the optical (VI), NIR (JHK), and MIR ([3.6] and [4.5]) bandpasses. These calibrations utilize stars +0.3 ± 0.1 mag below the tip, providing a substantial statistical improvement over previous calibrations which only used the sample of stars narrowly encompassing the tip.

Keywords: Red giant branch, Distance indicators
Verification of Gaia Data Release 3 Single-lined Spectroscopic Binary Solutions With Three Transiting Low-mass Secondaries. While secondary mass inferences based on single-lined spectroscopic binary (SB1) solutions are subject to $\sin i$ degeneracies, this degeneracy can be lifted through the observations of eclipses. We combine the subset of Gaia Data Release 3 SB1 solutions consistent with brown dwarf-mass secondaries with the Transiting Exoplanet Survey Satellite (TESS) Object of Interest (TOI) list to identify three candidate transiting brown dwarf systems. Ground-based precision radial velocity follow-up observations confirm that TOI-2533.01 is a transiting brown dwarf with $M={72}_{-3}^{+3}\,{M}_{\mathrm{Jup}}={0.069}_{-0.003}^{+0.003}\,{M}_{\odot }$ orbiting TYC 2010-124-1 and that TOI-5427.01 is a transiting very low-mass star with $M={93}_{-2}^{+2}\,{M}_{\mathrm{Jup}}={0.088}_{-0.002}^{+0.002}\,{M}_{\odot }$ orbiting UCAC4 515-012898. We validate TOI-1712.01 as a very low-mass star with $M={82}_{-7}^{+7}\,{M}_{\mathrm{Jup}}={0.079}_{-0.007}^{+0.007}\,{M}_{\odot }$ transiting the primary in the hierarchical triple system BD+45 1593. Even after accounting for third light, TOI-1712.01 has a radius nearly a factor of 2 larger than predicted for isolated stars with similar properties. We propose that the intense instellation experienced by TOI-1712.01 diminishes the temperature gradient near its surface, suppresses convection, and leads to its inflated radius. Our analyses verify Gaia DR3 SB1 solutions in the low Doppler semiamplitude limit, thereby providing the foundation for future joint analyses of Gaia radial velocities and Kepler, K2, TESS, and PLAnetary Transits and Oscillations light curves for the characterization of transiting massive brown dwarfs and very low-mass stars.

Keywords: Brown dwarfs, Substellar companion stars, Stellar radii, Spectroscopic binary stars, Low mass stars, Eclipsing binary stars, Trinary stars
An Investigation of New Brown Dwarf Spectral Binary Candidates From the Backyard Worlds: Planet 9 Citizen Science Initiative. We present three new brown dwarf spectral-binary candidates: CWISE J072708.09-360729.2, CWISE J103604.84-514424.4, and CWISE J134446.62-732053.9, discovered by citizen scientists through the Backyard Worlds: Planet 9 project. Follow-up near-infrared spectroscopy shows that each of these objects is poorly fit by a single near-infrared standard. We constructed binary templates and found significantly better fits, with component types of L7+T4 for CWISE J072708.09-360729.2, L7+T4 for CWISE J103604.84-514424.4, and L7+T7 for CWISE J134446.62-732053.9. However, further investigation of available spectroscopic indices for evidence of binarity and large amplitude variability suggests that CWISE J072708.09-360729.2 may instead be a strong variability candidate. Our analysis offers tentative evidence and characterization of these peculiar brown dwarf sources, emphasizing their value as promising targets for future high-resolution imaging or photometric variability studies.

Keywords: Brown dwarfs, L dwarfs, Binary stars, T dwarfs
Exploring Climate with Obliquity in a Variable-eccentricity Earth-like World. Exploring planetary systems similar to our solar system can provide a means to explore a large range of possibly temperate climates on Earth-like worlds. Rather than run hundreds of simulations with different eccentricities at fixed obliquities, our variable-eccentricity approach provides a means to cover an incredibly large parameter space. Herein Jupiter's orbital radius is moved substantially inward in two different scenarios, causing a forcing on Earth's eccentricity. In one case, the eccentricity of Earth varies from 0 to 0.27 over ~7000 yr for three different fixed obliquities (0°, 23°, and 45°). In another case, the eccentricity varies from 0 to 0.53 over ~9400 yr in a single case with zero obliquity. In all cases, we find that the climate remains stable, but regional habitability changes through time in unique ways. At the same time, the moist greenhouse state is approached but only when at the highest eccentricities.

Keywords: Exoplanet astronomy, Exoplanet atmospheres, Exoplanet dynamics
An Exploration of AGN and Stellar Feedback Effects in the Intergalactic Medium via the Low-redshift Lyα Forest. We explore the role of galactic feedback on the low-redshift Lyα (Lyα) forest (z ≲ 2) statistics and its potential to alter the thermal state of the intergalactic medium. Using the Cosmology and Astrophysics with Machine Learning Simulations (CAMELS) suite, we explore variations of the AGN and stellar feedback models in the IllustrisTNG and Simba subgrid models. We find that both AGN and stellar feedback in Simba play a role in setting the Lyα forest column density distribution function (CDD) and the Doppler width (b-value) distribution. The Simba AGN jet feedback mode is able to efficiently transport energy out to the diffuse IGM, causing changes in the shape and normalization of the CDD and a broadening of the b-value distribution. We find that stellar feedback plays a prominent role in regulating supermassive black hole growth and feedback, highlighting the importance of constraining stellar and AGN feedback simultaneously. In IllustrisTNG, the AGN feedback variations explored in CAMELS do not affect the Lyα forest, but varying the stellar feedback model does produce subtle changes. Our results imply that the low-z Lyα forest can be sensitive to changes in the ultraviolet background, stellar and black hole feedback, and that AGN jet feedback in particular can have a strong effect on the thermal state of the IGM.

Keywords: Cosmology, Supermassive black holes, Stellar feedback, Lyman alpha forest, Intergalactic gas, Active galactic nuclei, Intergalactic medium, Extragalactic astronomy
Multicolor Photometry of Tiny Near-Earth Asteroid 2015 RN<SUB>35</SUB> across a Wide Range of Phase Angles: Possible Mission-accessible A-type Asteroid. Studying small near-Earth asteroids is important in order to understand their dynamical histories and origins as well as to mitigate the damage caused by asteroid impacts on Earth. We report the results of multicolor photometry of the tiny near-Earth asteroid 2015 RN35 using the 3.8 m Seimei telescope in Japan and the TRAPPIST-South telescope in Chile over 17 nights in 2022 December and 2023 January. We observed 2015 RN35 across a wide range of phase angles from 2° to 30° in the g, r, i, and z bands in the Pan-STARRS system. These lightcurves show that 2015 RN35 is in a nonprincipal axis spin state with two characteristic periods of 1149.7 ± 0.3 s and 896.01 ± 0.01 s. We found that the slope of the visible spectrum of 2015 RN35 is as red as asteroid (269) Justitia, one of the very red objects in the main belt, which indicates that 2015 RN35 can be classified as an A- or Z-type asteroid. In conjunction with the shallow slope of the phase curve, we suppose that 2015 RN35 is a high-albedo A-type asteroid. We demonstrated that surface properties of tiny asteroids could be well constrained by intensive observations across a wide range of phase angles. 2015 RN35 is a possible mission-accessible A-type near-Earth asteroid with a small Δv of 11.801 km s-1 in the launch window between 2030 and 2035.

Keywords: Near-Earth objects, Multi-color photometry, Asteroids, Light curves, Photometry
Optimization of Future Multifilter Surveys Toward Asteroid Characterization. The aim of this paper is to find a set of photometric passbands that will give optimal results for spectrophotometric classification of asteroids into taxonomic types and classes. For this purpose various machine-learning methods are used, namely multinomial logistic regression, naive Bayes, support vector machines, gradient boosting, and multilayer perceptrons. Sequential feature selection is performed to assess the contribution of each reflectance difference. We find that to determine the taxonomic complexes with a balanced accuracy of 85%, a set of five spectrophotometric bands is required. For taxonomy type determination with the balanced accuracy of 80% a set of eight bands is necessary. Furthermore, only a three-band system is enough for distinguishing the C-complex asteroids with 92% balanced accuracy. These results can be used for designing future asteroid multifilter sky surveys.

Keywords: Multi-color photometry, Spectroscopy, Asteroid surfaces