175 papers
Despite searching for methanol in the water-rich protoplanetary disk around HL Tau using ALMA archival data, the study found no emission and derived stringent upper limits on its abundance, suggesting that optically thick dust obscures the signal or that the disk's chemical evolution differs significantly from other young stellar objects and comets.
This paper introduces a novel community detection framework that models solar vortices as an interacting network, revealing that vortices identified as hubs, connectors, or peripherals within these communities exhibit greater persistence, height, and collective helical motion, thereby offering new insights into how collective vortex dynamics drive energy transfer and wave excitation in the upper solar atmosphere.
This paper presents high-cadence near-infrared spectroscopy of the 2021 eruption of the recurrent nova RS Ophiuchi, characterizing the red giant secondary's pre-eruption state, the high-temperature coronal emission and continuum during the outburst, and potential post-eruption changes in the secondary star.
Two-dimensional particle-in-cell simulations reveal that magnetic reconnection generates strong out-of-plane magnetic fields within flux ropes through distinct mechanisms—specifically the Weibel instability driven by electron temperature anisotropy in the absence of a guide field and separatrix currents reinforced by the Kelvin-Helmholtz instability in its presence—which subsequently scatter electrons and influence heating processes.
This study demonstrates that the single-fluid magnetohydrodynamic approximation is a highly accurate and practical tool for modeling Alfvén wave propagation and energy transport in the partially ionized lower solar atmosphere, as it yields results nearly identical to more complex multi-fluid models despite minor discrepancies in high-frequency reflectivity and localized heating rates.
By analyzing 28 sharp-polarity-inversion-line delta sunspots, this study finds that only one originated from a single emerging writhe-kinked flux rope while the others formed through the merging of multiple magnetic regions, leading to the conclusion that such flux ropes are rarely the primary cause of these sunspots and that their genesis typically involves packing opposite-polarity flux via convection downflows.
This paper presents an autoencoder-based machine learning framework that effectively identifies anomalous stellar spectra, such as instrumental errors and rare carbon or oxygen-rich stars, within the MaNGA Stellar Library by leveraging reconstruction errors as anomaly scores.
This paper presents a transformer-based foundation model that leverages Gaia XP spectra and APOGEE data to simultaneously predict atmospheric parameters, mass, and age for evolved stars with high accuracy, demonstrating that data-driven approaches can effectively internalize stellar physics to overcome spectral degeneracies in Galactic archaeology.
This study utilizes LAMOST spectroscopic data to calibrate chromospheric activity indices for over 11,000 solar-like stars, revealing that activity levels increase with rotation rate until reaching a saturation threshold that varies systematically with effective temperature and convective zone depth.
Using 13 years of high-resolution SOPHIE spectroscopic data, this study identifies and characterizes distinct long-term magnetic activity cycles of approximately 4.8 and 4.9 years in the exoplanet-hosting M dwarfs GJ 617A and GJ 411, respectively, confirming their magnetic origin and distinguishing them from planetary signals to improve future exoplanet detection efforts.
Using JWST NIRSpec and MIRI observations, this study analyzes atomic hydrogen emission in scattered light from the Class 0 protostar L1527 IRS to characterize its magnetospheric accretion, estimating an accretion rate of approximately $1\times10^{-7}~ \text{M}_\odot \text{yr}^{-1}$ and discussing implications for non-steady, asymmetric accretion processes.
This study utilizes multi-wavelength thermal imaging to reveal that the archetypal Pictoris debris disk exhibits a vertically thicker mid-infrared structure compared to its millimeter counterpart, a finding that challenges collisional damping models and supports a scenario driven by radiation pressure, random collisions, and secular perturbations from inner giant planets.
This paper presents the Cataclysmic Variable Confident Catalogue (CCC), a comprehensive dataset of orbital periods for 910 cataclysmic variables and candidates derived from TESS observations, which validates existing measurements, corrects discrepancies, and provides new period determinations for the broader population.
This study demonstrates that homogeneous asteroseismic modeling of eight metal-poor, -enhanced evolved stars yields consistent fundamental properties regardless of whether -enhancement is treated fully or via ad hoc metallicity corrections, while also confirming a breakdown of the scaling relation at low metallicities that necessitates detailed modeling for accurate mass and age determinations.
This study demonstrates that late infall onto protoplanetary disks can generate distinct spiral structures observable in scattered light and CO line emission, with gradual gas accretion producing well-defined two-armed spirals and active streamer accretion creating flocculent patterns, while noting that these surface-level perturbations generally do not significantly disrupt the midplane unless the infalling mass rivals the disk mass.
This paper benchmarks pre-main sequence stellar evolutionary tracks by comparing HR diagram-derived masses with dynamical masses from ALMA disk observations of Upper Scorpius stars, finding that models with moderate spot coverage best match the data and that incorporating dynamical mass priors significantly reduces age scatter and improves model consistency.
By fitting a Gaussian mixture model to gravitational redshifts and Gaia-derived radii for 468 white dwarfs, this study demonstrates that evolutionary models assuming a thick, mass-dependent hydrogen envelope better match observational data than those with constant envelope masses, thereby validating gravitational redshift measurements as a powerful tool for constraining white dwarf hydrogen layer properties.
This paper presents theoretical and experimental evidence for a new phase of matter called multimodal superfluidity in neutron-rich systems, characterized by the coexistence of s-wave pairs, p-wave entangled double pairs, and quartets, which is predicted to occur in various fermionic systems and has significant implications for the structure and dynamics of neutron star crusts.
This paper introduces an automated density-based clustering method to quantify sunspot group nesting across 151 years of observations, revealing that approximately 60% of groups emerge in spatial-temporal nests, with nesting frequency and inter-nest spacing strongly correlated to solar activity levels.
This study presents new VLBA astrometry for 11 radio stars, achieving high-precision positions, parallaxes, and proper motions that significantly improve the alignment between the radio-based ICRF and the optical Gaia-CRF at the bright end.