Sazuna/UAT_keywords huggingface dataset:
Astrometric Accelerations of Provisional Targets for the Habitable Worlds Observatory. NASA's Habitable Worlds Observatory (HWO) will be the first space telescope capable of directly imaging Earth-like planets in the habitable zones (HZs) of Sun-like stars to probe their atmospheres for signs of life. Now in its early stages of design, a list of the 164 most promising targets for HWO has been released to the community to carry out precursor science. Massive companions in these systems—stars, brown dwarfs, or giant planets—could preclude the existence of Earth-sized planets in the HZ by impacting their long-term dynamical stability. Here, we use astrometry from Hipparcos and Gaia Early Data Release 3 (EDR3) to identify stars in the HWO preliminary target list that exhibit astrometric accelerations and determine joint constraints on the expected mass and separation of these companions. We find that 54 HWO targets have significant astrometric accelerations, 37 of which are accounted for by known giant planets and stellar companions. Follow-up efforts are required to clarify the specific nature of the suspected companions around the remaining 17 accelerating stars. Stars without significant accelerations are used to rule out large regions of companion mass and separation down to planetary masses. We find that with Hipparcos and Gaia EDR3 we are ∼85% sensitive to 2 M Jup planets between 4 and 10 au. Future Gaia releases will provide sensitivity to sub-Jovian-mass planets on solar system scales for provisional HWO targets. Finally, using analytical estimates of dynamical stability, we find that 13 HWO targets have known stellar or planetary companions that are likely to disrupt HZ planets.

Keywords: Astrometric exoplanet detection, Exoplanets, Astrometric binary stars, Space telescopes, Habitable planets
Validation of TESS Planet Candidates with Multicolor Transit Photometry and TRICERATOPS+. We present an upgraded version of TRICERATOPS, a software package designed to calculate false positive probabilities for planet candidates identified by the Transiting Exoplanet Survey Satellite (TESS). This enhanced framework now incorporates ground-based light curves in separate bandpasses, which are routinely obtained as part of the candidate vetting process. We apply this upgraded framework to explore the planetary nature of 14 TESS planet candidates, combining primarily J-band light curves acquired with the 200 inch Hale Telescope at Palomar Observatory with complementary archival observations from the Las Cumbres Observatory Global Telescope, the Fred Lawrence Whipple Observatory, and the Teide Observatory, along with existing TESS data and contrast curves from high-resolution imaging. As a result of this analysis we statistically validate (false positive probability &lt; 1.5% and nearby false positive probability &lt; 0.1%) six new planets in five systems: TOI-1346 b, TOI-1346 c, TOI-2719 b, TOI-4155 b, TOI-6000 b, and TOI-6324 b. For these systems, we provide updated estimates of their stellar and planetary properties derived from the TESS and ground-based observations. These new systems contain planets with radii between 0.9 and 6 R⊕ and orbital periods between 0.3 and 5.5 days. Finally, we use our upgraded version of TRICERATOPS to quantify the relative importance of multiwavelength transit photometry and high-resolution imaging for exoplanet candidate validation, and discuss which kinds of candidates typically benefit the most from ground-based multicolor transit observations.

Keywords: Broad band photometry, Light curves, Transits
A Multidata Approach to Open Clusters: Roslund 3 and Ruprecht 174 in CCD UBV and Gaia DR3 Context. A detailed analysis of the structural, astrophysical, kinematic, and dynamical properties of the open clusters Roslund 3 and Ruprecht 174 is carried out using CCD UBV photometry in conjunction with astrometric and photometric data from Gaia DR3. Membership probabilities were computed via the UPMASK algorithm applied to Gaia proper motions and trigonometric parallaxes, leading to the identification of 198 likely members for Roslund 3 and 397 for Ruprecht 174. Astrophysical parameters were derived using both the classical approach, where parameters are independently determined, and a Markov chain Monte Carlo technique, which estimates them simultaneously. The agreement between the results from both methods confirms their reliability and highlights the robustness of the classical method. The reddening values were determined as E(B ‑ V) = 0.410 ± 0.046 mag for Roslund 3 and E(B ‑ V) = 0.615 ± 0.042 mag for Ruprecht 174. The estimated distances are d = 1687 ± 121 pc for Roslund 3 and d = 2385 ± 163 pc for Ruprecht 174. Both clusters exhibit metallicities close to the solar value, with [Fe/H] = 0.030 ± 0.065 dex for Roslund 3 and [Fe/H] = 0.041 ± 0.064 dex for Ruprecht 174. The corresponding ages were found to be τ = 60 ± 6 and τ = 520 ± 50 Myr, respectively. The present-day mass function slopes were found to be 1.18 ± 0.13 for Roslund 3 and 1.53 ± 0.30 for Ruprecht 174, consistent with the canonical Salpeter value within uncertainties. Galactic orbital analyses indicate that both clusters are thin-disk members confined within the Solar circle. Additionally, relaxation times and spatial distributions of stars suggest that both clusters have reached dynamical relaxation and exhibit clear signs of mass segregation.

Keywords: Stellar kinematics, Open star clusters, Hertzsprung Russell diagram
A Pair of Dynamically Interacting Sub-Neptunes around TOI-6054. We confirm the planetary nature of a pair of transiting sub-Neptune exoplanets orbiting the bright F-type subgiant star TOI-6054 (V = 8.02, K = 6.673) as a part of the OrCAS radial velocity survey using WIYN/NEID observations. We find that TOI-6054b and TOI-6054c have radii of 2.64 ± 0.15R⊕ and 2.82 ± 0.17R⊕, respectively, and masses of 12.5 ± 1.7M⊕ and 9.3 ± 1.9M⊕. The planets have zero-albedo equilibrium temperatures of 1360 ± 32 K and 1143 ± 28 K. The host star has expanded and will evolve off of the main sequence within the next ∼500 Myr, and the resulting increase in stellar luminosity has more than doubled the stellar flux the two planets receive compared to the start of the host star's main-sequence phase. Consequently, TOI-6054b may be losing some of its primordial hydrogen/helium atmosphere—if it has one. Based on dynamical simulations performed using the orbital parameters of the two planets, TOI-6054b, and TOI-6054c are very likely in a 5:3 mean motion resonance. The TOI-6054 system thus has the potential to be an excellent candidate for future atmospheric follow-up observations, with two similarly sized sub-Neptunes around a bright star. We also estimate that if TOI-6054b is currently losing its H/He atmosphere, this should be observable from space and from the ground.

Keywords: Exoplanet dynamics, Transits, Exoplanets, Radial velocity, Exoplanet systems, Exoplanet astronomy, Exoplanet detection methods
WF-SwinUnet: A Window Fusion-based RFI Segmentation Model and Its Application in FAST. A key challenge in ensuring the quality of high-sensitivity observations from the Chinese Sky Eye FAST is the efficient suppression of radio frequency interference (RFI). However, the traditional thresholding method cannot adapt to the complex baseline noise because it relies on manual parameter adjustment and assumes a constant threshold value, it also faces bottlenecks such as the failure to detect weak interferences and the ambiguous positioning of the boundary. This paper proposes a deep learning framework (WF-SwinUnet) based on the multiwindow fusion Swin Transformer, which achieves end-to-end accurate RFI segmentation through the collaborative design of an adaptive multiscale window mechanism and a bottleneck residual network. Experiments show that compared with the SumThreshold method, this model improves the accuracy, recall and F1 score by 23.4%, 32.1%, and 30.1%, respectively, improves the processing efficiency by 60% (reducing the time from 10,440.95 to 4387.87 ms), and significantly improves the accuracy of boundary positioning, reducing the boundary error (HD95) by 73.6% compared with ArPLS-ST. For weak narrowband RFI (signal strength close to background noise), which is difficult to detect with traditional methods, the model F1 score reaches 0.6808, avoiding signal loss due to threshold overload. In addition, among the six FAST observation targets, the model's average F1 score reached 0.818, an improvement of 8.3% over the existing best deep learning model (RFI-Net). Ablation experiments verified the synergistic effect of the multiwindow fusion mechanism and the residual module, which together improved the overall performance by 21%.

Keywords: Radio telescopes
Magnetic Field of a Ring-like Molecular Cloud. We present a detailed study of the magnetic field structure in the G111 molecular cloud, a ring-like filamentary cloud within the NGC 7538 region. Our analysis combines multiwavelength polarization data and molecular-line observations to investigate the magnetic field's role in the cloud's formation and evolution. We utilized interstellar dust polarization from the Planck telescope to trace large-scale field orientations, starlight extinction polarization from the Kanata telescope to probe the cloud's magnetic field after foreground subtraction, and velocity gradients derived from CO isotopologues observed with the IRAM 30 m telescope to examine dense regions. Our results reveal a coherent yet spatially varying magnetic field within G111. The alignment between Planck-derived orientations and starlight extinction polarization highlights significant foreground dust contamination, which we correct through careful subtraction. The global alignment of the magnetic field with density structures suggests that the field is dynamically important in shaping the cloud. Variations in CO-derived orientations further suggest that local dynamical effects, such as gravitational interactions and turbulence, influence the cloud's structure. The curved magnetic field along the dense ridges, coinciding with mid-infrared emission in WISE data, indicates shock compression, likely driven by stellar feedback or supernova remnants. Our findings support a scenario where G111's morphology results from turbulent shock-driven compression, rather than simple gravitational contraction. The interplay between magnetic fields and external forces is crucial in shaping molecular clouds and regulating star formation. Future high-resolution observations will be essential to further constrain the magnetic field's role in cloud evolution.

Keywords: Interstellar magnetic fields, Interstellar filaments, Polarimetry, Molecular clouds
BLADE: An Automated Framework for Classifying Light Curves from the Center for Near-Earth Object Studies Fireball Database. Fireballs (bolides) are high-energy luminous phenomena produced when meteoroids and small asteroids enter Earth's atmosphere at hypersonic speeds, often resulting in fragmentation or complete disintegration accompanied by significant energy release. The resulting bolide light curves capture temporal brightness variations as these objects traverse increasingly dense atmospheric layers, providing essential information on meteoroid entry dynamics, fragmentation behavior, and atmospheric energy deposition processes. The Center for Near-Earth Object Studies' (CNEOS) continuously expanding fireball database offers a globally comprehensive archive of bolide events, including light curves and associated metadata. Events associated with infrasound detections allow direct correlations between acoustic signatures and light curve features, therefore enabling detailed analyses of fragmentation dynamics and energy deposition. Here, we introduce Bolide Light-curve Analysis and Discrimination Explorer (BLADE), a robust and high-fidelity framework specifically designed to analyze bolide light curves for objects detected from space. BLADE incorporates a processing pipeline integrating Savitzky–Golay filtering, prominence-based peak detection, and gradient analysis, enabling systematic identification and classification of fragmentation events and their associated energy release characteristics. Preliminary results demonstrate that BLADE reliably distinguishes distinct bolide behaviors, providing an objective, scalable methodology for characterization and analysis of large bolide light curve data sets. This foundational work establishes a novel pathway for advanced bolide research, with promising applications in planetary defense and global atmospheric monitoring. Future research should adopt an integrative approach combining CNEOS optical data with complementary infrasound measurements, further clarifying relationships between bolide energy deposition and acoustic signatures, thus refining our understanding of meteoroid and asteroid atmospheric entry processes.

Keywords: Light curve classification , Light curves, Asteroids, Meteoroids
Detailed Architecture of the L 98-59 System and Confirmation of a Fifth Planet in the Habitable Zone. The L 98-59 system, identified by TESS in 2019, features three transiting exoplanets in compact orbits of 2.253, 3.691, and 7.451 days around an M3V star, with an outer 12.83 day nontransiting planet confirmed in 2021 using ESPRESSO. The planets exhibit a diverse range of sizes (0.8─1.6 R⊕), masses (0.5─3 M⊕), and likely compositions (Earth-like to possibly water-rich), prompting atmospheric characterization studies with Hubble Space Telescope and JWST. Here, we analyze 16 new TESS sectors and improve radial velocity (RV) precision of archival ESPRESSO and HARPS data using a line-by-line framework, enabling stellar activity detrending via a novel differential temperature indicator. We refine the radii of L 98-59 b, c, and d to 0.837 ± 0.019 R⊕, 1.329 ± 0.029 R⊕, and 1.627 ± 0.041 R⊕, respectively. Combining RVs with transit timing variations (TTVs) of L 98-59 c and d from TESS and JWST provides unprecedented constraints on the masses and eccentricities of the planets. We report updated masses of 0.46 ± 0.11 M⊕ for b, 2.00 ± 0.13 M⊕ for c, and 1.64 ± 0.07 M⊕ for d, and a minimum mass of 2.82 ± 0.19 M⊕ for e. We additionally confirm L 98-59 f, a nontransiting super-Earth with a minimal mass of 2.80 ± 0.30 M⊕ on a 23.06 day orbit inside the Habitable Zone. The TTVs of L 98-59 c and d (&lt;3 minutes, PTTV = 396 days) constrain the eccentricities of all planets to near-circular orbits (e ≲ 0.04). An internal structure analysis of the transiting planets reveals increasing water-mass fractions ( fH2O ) with orbital distance, reaching  fH2O≍0.16  for L 98-59 d. We predict eccentricity-induced tidal heating in L 98-59 b with heat fluxes comparable to those of Io, potentially driving volcanic activity.

Keywords: M dwarf stars, Exoplanets, Super Earths, Transit timing variation method, Radial velocity, Transit photometry, Planetary interior
Neural Posterior Estimation for Cataloging Astronomical Images with Spatially Varying Backgrounds and Point Spread Functions. Neural posterior estimation (NPE), a type of amortized variational inference, is a computationally efficient means of constructing probabilistic catalogs of light sources from astronomical images. To date, NPE has not been used to perform inference in models with spatially varying covariates. However, ground-based astronomical images exhibit spatially varying sky backgrounds and point spread functions (PSFs), and accounting for this variation is essential for constructing accurate catalogs of imaged light sources. In this work, we introduce a novel NPE-based cataloging method that trains an inference network with semisynthetic astronomical images generated using PSFs and backgrounds sampled from the Sloan Digital Sky Survey. In experiments with semisynthetic images, we evaluate the method on key cataloging tasks: light source detection, star/galaxy separation, and flux measurement. A "generalist" inference network—trained with diverse PSFs and backgrounds—performs as well as a "specialist" network even when both are evaluated on the specialist's particular PSF/background combination. This result suggests that a single NPE network can generalize across spatial variations, eliminating the need for retraining on each observational condition.

Keywords: Astronomy image processing
JVLA Measurement of Grain Size in the Compact Dust Ring Around Class I Protostar WL 17. The maximum grain size in protoplanetary disks is a critical parameter for planet formation, as the efficiency of mechanisms like streaming instability and pebble accretion depend on grain size. Even young class 0/I objects, such as HL Tau, show substructures in their disks, indicating the potential for early planet formation. In this study, we investigated the grain size in the dust surrounding the class I object WL 17 using the Karl G. Jansky Very Large Array. Observations were conducted across seven frequency bands (Q, Ka, K, Ku, X, C, and S bands) ranging from 2 to 48 GHz, corresponding to wavelengths of 15 cm–6.3 mm, with a spatial resolution exceeding 0 .″ 5. While the ring structure at 0 .″ 1 of WL 17 remains unresolved in our data, its emission is clearly detected at all observed frequencies, except at 2 GHz. To estimate the maximum grain size ( amax ) within the ring, we compared the observed spectral energy distribution (SED) with theoretical SEDs calculated for various  amax  values using radiative transfer models. Assuming the dust opacity follows the DSHARP model, our analysis suggests that certain structures internal to the ring achieved a maximum grain size of approximately 4.2 mm. Additionally, we discuss the gravitational stability of the ring and the potential planetary core mass that could form through pebble accretion within the structure.

Keywords: Protoplanetary disks
Constructing a Pristine View of Extended Globular Cluster Structure. Globular clusters (GCs) displaying extended structures are becoming increasingly ubiquitous in the Milky Way (MW). Despite their low surface brightness, which makes disentangling the true structure from the MW overwhelming difficult, the increasing availability of multidimensional data sets has allowed for new detections of extended GC structure. This work utilises the Pristine-Gaia synthetic catalog released as part of the Pristine survey's first data release to search for tidally stripped stars in the peripheries of MW GCs. Pristine provides photometric [Fe/H] measurements based on CaHK-band photometry. Using unsupervised machine learning techniques, we provide lists of extratidal stars for 30 GCs, one of the largest surveys of its kind. We find that (1) 22 GCs that passed our quality cut have extended structure within 5 deg from the cluster centers, of which six are new tentative detections, and (2) four of those GCs exhibit diffuse-envelope-like extratidal features, while the remaining GCs exhibit tidal-tail-like structures. We measure the position angles of the extended structures, find broad consistency between the position angles and the GC orbits, and discuss our results concerning N-body models. This work demonstrates the effectiveness of adding photometric metallicities to the multidimensional search of extended tidal structure and how the upcoming multi-object spectrographs will be crucial for exploring GC peripheries in the coming years.

Keywords: Globular star clusters, Stellar photometry, Stellar abundances, Galactic archaeology, Stellar astronomy
An Advanced Deep Learning Model for Identifying Blue Horizontal-branch Stars from LAMOST DR10. Blue horizontal-branch (BHB) stars are ideal tracers for studying the kinematics and structural properties of the Milky Way. With massive spectral data provided by the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), we aim to identify more potential BHB stars using machine learning methods. In this study, we propose BHBNet, an advanced two-stage deep learning model integrating multiple techniques. By implementing Bayesian inference, it not only provides classification results but also quantifies uncertainty. In stage 1, a six-class classification model was constructed to initially identify BHB candidates, achieving a precision of 95.43% on the test set. In stage 2, a binary classification model constructed through the transfer learning method was employed to further refine the candidates, achieving a precision of 98.36% on the test set. Subsequently, by performing a two-stage search in LAMOST low-resolution survey DR10, we identified 6792 candidates. Nevertheless, since the completeness of this search result has not been assessed, these samples may not be adequate for statistical studies of the BHB population. We analyzed candidate properties including color, absolute magnitude, and spatial distribution, while estimating their atmospheric parameters. Eventually, by fitting Balmer line profiles, we identified 1605 new BHB stars compared to the previous studies by X.-X. Xue et al. and J. J. Vickers et al. Our study emphasizes the potential and effectiveness of using machine learning methods in identifying and analyzing BHB stars.

Keywords: Horizontal branch stars, Convolutional neural networks, Astronomy data analysis, Astrostatistics
A Semiempirical Estimate of Solar Extreme-ultraviolet Evolution from 10 Myr to 10 Gyr. The extreme-ultraviolet (EUV; 100─911 Å) spectra of F, G, K, and M stars provide diagnostics of the stellar chromosphere through the corona, with line and continuum formation temperatures spanning roughly 104─107 K. The EUV stellar spectrum in turn drives atmospheric photochemistry and numerous escape processes on orbiting planets, and is often combined with the stellar X-ray flux to make up the X-ray and ultraviolet (XUV) irradiance. However, very few direct EUV spectra of other stars exist in the archive, and as a result, X-ray scaling relations are often assumed for the XUV evolution of cool stars. In this work, we present a new study of the EUV history of solar-type stars, using scaling relations based on transition region/coronal far-ultraviolet emission lines and differential emission measure-based synthetic spectra to provide a semiempirical estimate of the EUV evolution of the Sun over the ≍10 Myr─10 Gyr age range for the first time. We utilize new and archival Hubble Space Telescope observations of solar analogs (T⊙ ± 150 K for stars older than 100 Myr) and "Young Suns" (age &lt; 100 Myr) that will evolve into main-sequence early G-type stars to predict the 90─360 Å EUV flux from a sample of 23 stars. We find that the EUV activity evolution for solar-type stars follows a two-component behavior: a saturated L(EUV)/Lbol plateau (at a level of about 10−4) followed by a power-law decay (α ≍ −1.1) after ages of ≍50─100 Myr. Consequently, the EUV flux incident at 1 au around solar analogs varies over the lifetime of the Sun, ranging from 100× the present-day UV irradiance at 10 Myr to 0.3× the present-day level at 10 Gyr. We find that the EUV luminosity is approximately the same as the soft X-ray luminosity up to approximately 1 Gyr, after which the EUV luminosity of the stars dominates. In comparison to Sun-like stars, the EUV saturation level of early/mid M dwarfs is several times higher and lasts ∼10─20 times longer.

Keywords: Exoplanet atmospheres, Solar extreme ultraviolet emission, Stellar activity