Sazuna/UAT_keywords huggingface dataset:
Evidence for a Nonzero Eccentricity Superpuff Exoplanet WASP-107 b Using JWST Occultation Observation. WASP-107 b is an extremely low-density superpuff exoplanet whose inflated radius and evidence of strong internal heating make it a key target for understanding planetary structure and evolution. Its orbital eccentricity is a critical parameter for testing mechanisms such as tidal heating and high-eccentricity migration, yet previous measurements have remained inconclusive. Due to the large radial velocity jitter caused by stellar activity, and the presence of at least one additional planet in the system, previous radial velocity measurements could not robustly determine the eccentricity of WASP-107 b. Here, we combine the new JWST secondary eclipse data with transit timing data from the Hubble Space Telescope, TESS, and JWST to measure the eccentricity of WASP-107 b. Our joint analysis shows that WASP-107 b has an eccentricity of 0.09 ± 0.02, a mass of 0.096 ± 0.005 MJ, and an orbital period of 5.721487 ± 0.000001 days. We find the 99.7% lower limit of the eccentricity is about 0.04. These new measurements are consistent with the scenario in which WASP-107 b is in the final stage of high-eccentricity migration. A preliminary estimate shows that eccentricity-driven tidal dissipation can provide a significant contribution to the energy required to sustain the observed radius inflation of WASP-107 b. Our results establish the dynamical status of one of the most intriguing low-density exoplanets known and offer new insights into its formation and evolution history.

Keywords: Transits, Hubble Space Telescope, Exoplanet systems, James Webb Space Telescope, Eccentricity
JWST and HST Observations of the Host Galaxy and Supernova SN 2024aihh in EP240801a at z = 1.67. We present James Webb Space Telescope (JWST) and Hubble Space Telescope (HST) observations of the counterpart of EP 240801a, at z = 1.67, the first fast X-ray transient (FXT) identified as an X-ray flash by the Einstein Probe and Fermi Gamma-Ray Burst Monitor. Our observations reveal strong photometric and spectroscopic evidence for an associated broad-lined Type Ic supernova (SN) SN 2024aihh, the most distant spectroscopically identified gamma-ray-burst (GRB)─SN to date. The SN exhibits similar luminosity and light-curve evolution to the prototype GRB-SN 1998bw with an absolute magnitude of the SN at ∼23 days rest frame of MF140W ≍ −19 mag. The SN is located in a host galaxy with complex morphology at a large (∼6 kpc) offset in a region of relatively low surface brightness. The region around the SN has a modest star formation rate and is dominated by an intermediate mass-weighted age (1.4 ± 0.3 Gyr) population, despite the apparent presence of a young, massive broad-lined Type Ic SN progenitor. These observations demonstrate that observations with HST and JWST can greatly extend the redshift range over which the GRB/FXT-SN connection can be studied, including in relatively low-luminosity, X-ray-rich events. They demonstrate little apparent evolution in the SN properties from local examples despite EP 240801a originating from an epoch 10 Gyr ago.

Keywords: Type Ic supernovae, Gamma-ray bursts, Hubble Space Telescope, X-ray transient sources, James Webb Space Telescope
MUSEQuBES: Physical Conditions, Origins, and Multielement Abundances of the Circumgalactic Medium of an Isolated, Star-forming Dwarf Galaxy at z = 0.57. In dwarf galaxy models, outflows expel metal-enriched interstellar medium (ISM) into the circumgalactic medium (CGM) to reproduce their observed low metallicities, but measurements of dwarf CGM properties are scarce. We present a study of the CGM of an isolated dwarf at z = 0.5723 with a stellar mass of ≍5 × 107 M⊙ and star formation rate (≍0.05 M⊙ yr−1) and ISM metallicity ([O/H] ≍ −0.9) consistent with the star-forming main sequence and mass─metallicity relation. A background quasar sight line with archival UV spectra probes the dwarf's CGM at a projected distance of 28 kpc, corresponding to approximately half of the estimated virial radius. The dwarf's CGM is detected in H I; intermediate metal ions of C III, O III, O IV, and S V; and kinematically broader, highly ionized O VI but is undetected in N IV and Ne VIII. Photoionization modeling of the intermediate ions indicates a modest volume filling factor (∼6% along the sight line or ∼2% globally) and a mass of ∼2 × 108 M⊙, ∼4× higher than the dwarf's stellar mass but ∼10× less than the highly ionized CGM. The O VI kinematics are comparable to the dwarf's estimated virial velocity, suggesting that it is likely associated with cool, photoionized, and volume-filling CGM, with bulk motion or turbulence dominating over thermal pressure. The metallicity inferred for the intermediate ions is [O/H] = −0.6, but with low relative abundances of [C/O] = −0.6 and [N/O] &lt; −1.0. The [N/O] is below levels expected of the dwarf's ISM but consistent with core-collapse supernova ejecta, suggesting that supernova-enriched gas escaped the dwarf without mixing significantly with ISM enriched in nitrogen from evolved, low-mass stars.

Keywords: Intergalactic medium, Dwarf galaxies, Chemical abundances, Circumgalactic medium
The Role of Self-gravity in Debris-disk Warp Formation: The Case of HD 110058. We investigate the crucial role of self-gravity in the formation of warps in debris disks, focusing on the HD 110058 system as an example. Using advanced graphical-processing-unit-accelerated N-body simulations, we model the gravitational dynamics of a massive planetesimal disk perturbed by an inclined inner planet. Our simulations reveal that self-gravity fundamentally alters the disk's evolution compared to massless models. It enforces a coherent semirigid precession of the disk and enables the rapid formation of a global warp structure within 0.5 Myr. The warp angle undergoes a damped oscillation, eventually settling into a quasi-equilibrium state. By generating synthetic scattered-light images, we demonstrate that our model successfully reproduces the observed S-shaped warp morphology of the debris disk in HD 110058, supporting the existence of an unseen planet. Furthermore, we derive an empirical relationship that connects the equilibrium warp angle to the physical parameters of the disk and the planet. Applying this relation to HD 110058, we constrain its disk mass to be likely less than 1000 M⊕, offering a new dynamical perspective on the debris-disk mass problem.

Keywords: Exoplanet dynamics, Debris disks, N-body simulations, Circumstellar disks
First Mapping of Prebiotic Molecule CH<SUB>2</SUB>NH in a Prestellar Core. We present the first spatially resolved map of methanimine (CH2NH) in the prestellar core L1544 using the IRAM 30 m telescope. The 20,2─10,1 line at 127 GHz was mapped with 20″ resolution (∼2800 au), revealing extended CH2NH emission across the core. The peak line intensity coincides with the well-known c-C3H2 peak, while the integrated intensity peaks between the HNCO and dust continuum peaks due to broader linewidths in the latter region. Column densities of CH2NH are ∼(0.5─1.4×)1012 cm−2, corresponding to fractional abundances of 5 × 10−11─1 × 10−10, with a trend decreasing from the southern, carbon-chain rich region to the dust and HNCO peak in the north. Comparison with complementary molecular maps and the gas-grain chemical model of Sipilä et al. suggests that neutral─neutral gas-phase reactions and dissociative recombination dominate in the outer carbon-chain shell. This study demonstrates that CH2NH, a simple nitrogen- and carbon-bearing molecule previously detected with pointed observations in other cold cores, is present and spatially extended in the evolved prestellar core L1544. This indicates that prebiotic nitrogen-carbon chemistry continues efficiently up to the onset of gravitational collapse, providing key constraints for astrochemical models and the early stages of chemical complexity leading to amino acids.

Keywords: Pre-biotic astrochemistry
Lightcurves, Rotation Periods, and Colors for Vera C. Rubin Observatory's First Asteroid Discoveries. We present lightcurves, rotation periods, and colors for the first asteroid discoveries made with the NSF-DOE Vera C. Rubin Observatory. These are the first science results derived from the 2103 asteroid discoveries released as part of the Rubin First Look (RFL) media event on 2025 June 23, in which the first LSST Camera commissioning images were released. The ∼340,000 observations in which the discoveries were made span nine nights between 2025 April 21 and May 5. With a limiting single-epoch 5σ depth of ∼23─25 mag and dense temporal sampling under an irregular, commissioning-driven cadence, the RFL observations provide an ideal test bed for determination of rotation periods, including sensitivity to rapid rotation. We model lightcurves and derive rotation periods and colors for the ∼2000 objects. We find 75 main-belt asteroids (MBAs) and one near-Earth object (NEO) with reliable rotation periods spanning 0.031─21.3 hr and a photometric precision in the range of 0.05─0.15 mag. We find 19 superfast rotators with periods shorter than the 2.2 hr spin barrier. Rubin-discovered MBA 2025 MN45 is the fastest-rotating d &gt; 0.5 km known asteroid with a rotation period of 1.9 minutes; along with NEO 2025 MJ71 (1.9 minutes) and Rubin-discovered MBAs 2025 MK41 (3.8 minutes), 2025 MV71 (13 minutes), and 2025 MG56 (16 minutes), these five super- to ultrafast rotators join a couple of NEOs as the fastest-spinning subkilometer asteroids known. As this study demonstrates, even in early commissioning, Rubin is successfully probing a previously sparsely sampled region of the subkilometer size−spin rate regime for MBAs.

Keywords: Small Solar System bodies, Optical astronomy, Light curves, Two-color diagrams, Main belt asteroids, Asteroid rotation, Photometry
Interstellar Comet 3I/ATLAS: Evidence for Galactic Cosmic-Ray Processing. Spectral observations of 3I/ATLAS (C/2025 N1) with JWST/NIRSpec and SPHEREx reveal an extreme CO2 enrichment (CO2/H2O = 7.6 ± 0.3) that is 4.5σ above solar system comet trends and among the highest ever recorded. This unprecedented composition, combined with substantial absolute CO levels (CO/H2O = 1.65 ± 0.09) and red spectral slopes, provides direct evidence for galactic cosmic-ray (GCR) processing of the outer layers of the interstellar comet nucleus. Laboratory experiments demonstrate that GCR irradiation efficiently converts CO to CO2 while synthesizing organic-rich crusts, suggesting that the outer layers of 3I/ATLAS consist of irradiated material whose properties are consistent with the observed composition of the 3I/ATLAS coma and with its observed spectral reddening. Estimates of the erosion rate of 3I/ATLAS indicate that current outgassing samples the GCR-processed zone only (depth ∼15─20 m), never reaching pristine interior material. Outgassing of pristine material after perihelion remains possible, though it is considered unlikely. This points to a paradigm shift: long-residence interstellar objects likely reveal primarily GCR-processed material rather than pristine material representative of their primordial formation environments. With 3I/ATLAS approaching perihelion in 2025 October, immediate follow-up observations are critical to confirm this interpretation and establish GCR processing as a fundamental evolutionary pathway for interstellar objects.

Keywords: Comet nuclei, Galactic cosmic rays, Interstellar objects, Comets, Cosmic rays
Formation of a Magnetic Flux Rope prior to the Eruption: Insight from a Radiative MHD Simulation of Active Region Emergence. Magnetic flux ropes are fundamental magnetic structures in solar eruptions, whose formation is generally attributed to: (1) the emergence of subsurface flux tubes; or (2) flux cancellation driven by photospheric horizontal flows and magnetic reconnection. Both mechanisms can operate simultaneously during active region (AR) evolution, making their relative contributions challenging to quantify. Here, we analyze the formation of a flux rope in a MURaM radiative magnetohydrodynamic simulation, which formed and evolved for approximately 3 hr before an M-class flare. The formation process is quantified by the magnetic helicity flux, which drives the nonpotential evolution of the magnetic field, with its advection and shear terms on the photosphere corresponding to the emergence and photospheric horizontal flows, respectively. Examining the helicity injected into the flux rope through the photosphere, we find both terms increase significantly as the eruption approaches, with the shear term prevailing overall. Height-dependent analysis of the helicity flux, together with the magnetic field and velocity distributions, further reveals a gradual transition from the shear to the advection term with an increasing altitude, which is driven by magnetic reconnection above the photosphere. Our results provide quantitative evidence that flux cancellation governs flux rope formation, arising naturally from magnetic field reorganization during AR evolution: as the flux emergence transports the magnetic flux upward, photospheric shearing motions adjust the magnetic field and inject helicity into the solar atmosphere, and magnetic reconnection ultimately assembles the main body of flux ropes.

Keywords: Solar magnetic flux emergence, Solar photosphere, Solar convective zone, Solar active regions, Solar magnetic fields
Evidence for In Situ Particle Energization during the 2024 May Event Based on the ASPEX Instrument on Board Aditya-L1. The interaction between interplanetary coronal mass ejection (ICME) structures can alter the geoeffectiveness of the ICME events in myriad ways. Many aspects of these interaction processes are not well understood. Using the energy spectra measured in two mutually orthogonal top-hat analyzers (THA-1 and 2), which are part of the Solar Wind Ion Spectrometer subsystem of the Aditya Solar Wind Particle EXperiment (ASPEX) on board India's Aditya-L1 mission, we gain insights into intricate features of ICME─ICME interactions during the 2024 May solar event. We report here an unprecedented two-orthogonal-plane perspective of ICME─ICME interactions for the first time from the L1 point. The investigation reveals a special interaction region formed by the propagation of the forward shock driven by complex ejecta in the preceding ICME. The interaction causes the formation of a downstream region spanning over 13 hr, which propagates in the interplanetary medium. The observations reveal that this region serves as a site for proton and alpha particle energization, and the particles within this region get distributed from one plane to the other. The presence of forward shock and particle energization is confirmed by the energetic particle flux measurements by the SupraThermal and Energetic Particle Spectrometer of ASPEX. These observations provide an unprecedented perspective on how solar wind ions become energized and distributed in an ICME─ICME interaction region.

Keywords: Interplanetary shocks, Solar wind, Solar physics, Solar coronal mass ejections, Solar storm
Gaia Barium Dwarfs and Their Ostensibly Ordinary Counterparts. The recently identified Gaia population of main-sequence─white dwarf (MS+WD) binaries at separations of ∼1 au, often with moderate eccentricities, is not readily reproduced by binary population synthesis models. Barium (Ba) stars represent a closely related population whose enrichment in s-process elements both confirms the presence of a WD companion and attests to past binary interaction. It also indicates that mass transfer occurred at least during the late- and post─asymptotic giant branch (AGB) phases of the WD progenitor, when s-process elements are dredged up. In this work, we further explore the connection between the astrometrically identified Gaia MS+WD binaries and the classical Ba star population. To achieve this, we used high-resolution Fiber-fed Extended Range Optical Spectrograph spectroscopy to measure abundances for 30 Gaia Data Release 3 nonsingle-star binaries, identifying 14 as Ba-enriched. Together with our recent analysis of archival GALAH data, this yields a sample of 40 Ba dwarfs with dynamically measured WD masses, compared to only 6 previously known systems with known WD masses at these separations. We find that, in cases where metallicity is sufficiently low to facilitate efficient s-process production, Ba and yttrium enrichment is often detected. This enrichment is also identified in eccentric systems, suggesting that post-AGB mass transfer mechanisms are capable of pumping eccentricity into the orbit or occur without erasing it. Our results indicate that the Gaia MS+WD binaries trace the population from which Ba stars emerge. Treating the large Gaia-discovered population as an extension of known s-process enriched dwarfs opens an avenue to empirically constrain their formation and evolution.

Keywords: Post-asymptotic giant branch stars, White dwarf stars, Interacting binary stars, Chemical enrichment, Astrometric binary stars, Barium stars, S-process
GRB 250704B: An Off-axis Short GRB with a Long-lived Afterglow Plateau. We present a detailed multiwavelength afterglow study of the short gamma-ray burst (GRB) GRB 250704B, extensively monitored in optical and near-infrared bands. Its afterglow displays an unusually long duration plateau followed by an achromatic break and a steep decline, deviating from canonical GRB afterglows. While long plateaus are often explained by central engine activity, we find that for GRB 250704B an energy injection model requires unreasonable parameters. The afterglow is better explained by an off-axis power-law structured jet with a narrow core (θc ≍ 0 .° 7) viewed at a modest angle (θv ≍ 1 .° 9). A comparison with GRB 170817A shows that both events are consistent with the off-axis structured jet scenario, where the shape of the light curve is governed primarily by the geometry of the jet and the viewing angle rather than the energetics, microphysical parameters, or external density. Our results underscore the importance of incorporating the jet structure in GRB modeling.

Keywords: Gamma-ray sources, Gamma-ray astronomy, Astronomical methods, Optical astronomy
Compelling Evidence for a Harmonic in the Light Curve of the Supermassive Black Hole Binary Candidate PKS J1309+1154. We recently discovered a supermassive black hole binary (SMBHB) candidate, PKS J1309+1154, in the combined 46 yr University of Michigan Radio Astronomy Observatory (UMRAO) plus Owens Valley Radio Observatory (OVRO) blazar monitoring programs at 14.5/15 GHz. The light curve of PKS 1309+1154 exhibits a 17.9 yr periodicity. We also reported a hint of a first harmonic with a 9 yr periodicity in this object. Further analysis of the PKS J1309+1154 light curve provides compelling evidence that both the fundamental and the harmonic are real, confirming the existence of real periodicities in blazar light curves. This is the first case, to our knowledge, of watertight evidence for a fundamental periodicity and a harmonic periodicity in a blazar light curve. It makes PKS J1309+1154 a strong SMBHB candidate and thus the third such candidate to be revealed through long-term radio monitoring, the other two being PKS J0805─0111 and PKS 2131─021, both discovered through the OVRO 40 m Telescope monitoring program. It is argued that hundreds of SMBHB candidates will be discovered by the combination of the South Pole Telescope, the Vera Rubin Observatory, and the Simons Observatory. Coherent searches for gravitational waves from a network of SMBHB candidates, starting immediately, are strongly motivated.

Keywords: Supermassive black holes, Relativistic jets, Blazars
MAUVE-MUSE: A Star-formation-driven Outflow Caught in the Act of Quenching the Stripped Virgo Galaxy NGC 4064. The rapid quenching of satellite galaxies in dense environments is often attributed to environmental processes such as ram pressure stripping. However, stripping alone cannot fully account for the removal of dense, star-forming gas in many satellites, particularly in their inner regions. Recent models and indirect observations have suggested that star-formation-driven outflows may play a critical role in expelling this remaining gas, yet direct evidence for such feedback-driven quenching remains limited. Here we report the discovery of an ionized gas outflow in NGC 4064, a Virgo cluster satellite that has already lost most of its cold gas through environmental stripping. MUSE observations from the Multiphase Astrophysics to Unveil the Virgo Environment survey reveal a bipolar outflow driven by residual, centrally concentrated star formation in NGC 4064—despite its current star formation rate being ∼0.4 dex below the star-forming main sequence due to prior interaction with the cluster environment. The outflow's mass loading factor is ∼2, suggesting that stellar feedback could remove the remaining gas on timescales shorter than those required for depletion by star formation alone. These results demonstrate that even modest but centrally concentrated star formation can drive efficient feedback in stripped satellites, accelerating quenching in the final stages of their evolution.

Keywords: Galaxy quenching, Star formation, Galaxy evolution, Interstellar medium
One Latent to Fit Them All: A Unified Representation of Baryonic Feedback on Matter Distribution. Accurate and parsimonious quantification of baryonic feedback on matter distribution is of crucial importance for understanding both cosmology and galaxy formation from observational data. This is, however, challenging given the large discrepancy among different models of galaxy formation simulations and their distinct subgrid physics parameterizations. Using 5072 simulations from four different models covering broad ranges in their parameter spaces, we find a unified 2D latent representation. Compared to the simulations and other phenomenological models, our representation is independent of both time and cosmology, much lower dimensional, and disentangled in its impacts on the matter power spectra. The common latent space facilitates the comparison of parameter spaces of different models and is readily interpretable by correlation with each. The two latent dimensions provide a complementary representation of baryonic effects, linking black hole and supernova feedback to distinct and interpretable impacts on both the matter power spectrum and field level. Our approach enables developing robust and economical analytic models for optimal gain of physical information from data and is generalizable to other fields with significant modeling uncertainty.

Keywords: Cosmology, Hydrodynamical simulations, Stellar feedback, Large-scale structure of the universe, Convolutional neural networks, N-body simulations, Dimensionality reduction
Formation of Be Stars via Wind Accretion: Case Study on Black Hole + Be Star Binaries. Be stars are rapidly rotating main-sequence stars that play a crucial role in understanding stellar evolution and binary interactions. In this Letter, we propose a new formation scenario for black hole (BH) + Be star binaries (hereafter BHBe binaries), where the Be star is produced through the wind Roche lobe overflow (WRLOF) mechanism. Our analysis is based on numerical simulations of the WRLOF process in massive binaries, building on recent theoretical work. We demonstrate that the WRLOF model can efficiently form BHBe binaries under reasonable assumptions on stellar wind velocities. Using rapid binary population synthesis, we estimate the population of such systems in the Milky Way, predicting ∼1800−3200 currently existing BHBe binaries originating from the WRLOF channel. These systems are characterized by high eccentricities and exceptionally wide orbits, with typical orbital periods exceeding 1000 days and a peak distribution around ∼10,000 days. Due to their long orbital separations, these BHBe binaries are promising targets for future detection via astrometric and interferometric observations.

Keywords: Binary stars, Black holes, Stellar mass loss, Stellar winds, Wide binary stars, Be stars, Stellar evolution