Search Publications
Physically Motivated Deep Learning to Superresolve and Cross Calibrate Solar Magnetograms
Maloney, Shane A.; Muñoz-Jaramillo, Andrés; Wright, Paul J. +7 more
Superresolution (SR) aims to increase the resolution of images by recovering detail. Compared to standard interpolation, deep learning-based approaches learn features and their relationships to leverage prior knowledge of what low-resolution patterns look like in higher resolution. Deep neural networks can also perform image cross-calibration by l…
A Classification Catalog of Periodic Variable Stars for LAMOST DR9 Based on Machine Learning
Mei, Ying; Wang, Feng; Deng, Hui +4 more
Identifying and classifying variable stars is essential to time-domain astronomy. The Large Area Multi-Object Fiber Optic Spectroscopic Telescope (LAMOST) acquired a large amount of spectral data. However, there is no corresponding variable source-related information in the data, constraining LAMOST data utilization for scientific research. In thi…
Hot Stars in the GALEX Ultraviolet Sky Surveys (GUVcat_AISxSDSS_HS) and the Binary Fraction of Hot Evolved Stars
Bianchi, Luciana
We present a catalog of 71,364 pointlike UV sources with Sloan Digital Sky Survey (SDSS) photometry and GALEX far-UV (FUV)‑near-UV (NUV) ≤0.1 mag. The limit corresponds to stellar T eff ≳15,000‑20,000 K, slightly depending on gravity but nearly reddening independent for Milky Way‑type dust. Most sources are hot white dwarfs (WDs) and su…
IRIS2+: A Comprehensive Database of Stratified Thermodynamic Models in the Low Solar Atmosphere
De Pontieu, Bart; Gošić, Milan; Sainz Dalda, Alberto +1 more
We present the most comprehensive collection of stratified-in-optical-depth thermodynamic models of the lower solar atmosphere. This database, named IRIS2+, consists of 40,320 synthetic representative profiles (RPs) and their corresponding representative model atmospheres (RMAs). The latter result from inverting the observed RPs, which …
Multimode δ Sct stars from the Zwicky Transient Facility Survey
Wang, Shu; Deng, Licai; Luo, Yangping +3 more
We obtain the largest catalog of multimode δ Sct stars in the northern sky to date using the Zwicky Transient Facility (ZTF) Data Release 20. The catalog includes 2254 objects, of which 2181 are new to our study. Among these multimode δ Sct stars, 2142 objects are double-mode δ Sct, while 109 objects are triple-mode δ Sct and three are quadruple-m…
Lithium Abundances from the LAMOST Medium-resolution Survey Data Release 9
Gao, Qi; Shi, Jian-Rong; Li, Chun-Qian +9 more
Lithium is a fragile but crucial chemical element in the Universe, and exhibits interesting and complex behaviors. Thanks to the mass of spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) medium-resolution survey (MRS), we can investigate the lithium abundances in a large and diverse sample of stars, whi…
Infrared Properties of Carbon Stars in Our Galaxy
Suh, Kyung-Won
We explore the characteristics of carbon stars within our Galaxy through a comprehensive analysis of observational data spanning visual and infrared (IR) bands. Leveraging data sets from IRAS, the Infrared Space Observatory, Akari, the Midcourse Space Experiment, the Two Micron All Sky Survey, the Wide-field Infrared Survey Explorer (WISE), Gaia D…
Optical Variability of Gaia CRF3 Sources with Robust Statistics and the 5000 Most Variable Quasars
Makarov, Valeri V.
Using the light-curve time-series data for more than 11.7 million variable sources published in the Gaia Data Release 3, the average magnitudes, colors, and variability parameters have been computed for 0.836 million Gaia CRF objects, which are mostly quasars and active galactic nuclei (AGNs). To mitigate the effects of occasional flukes in the da…
An Empirical Sample of Spectra of M-type Stars with Homogeneous Atmospheric-parameter Labels
Luo, A. -Li; Kong, Xiao; Li, Yinbi +6 more
The discrepancies between theoretical and observed spectra, and the systematic differences between various spectroscopic parameter estimates, complicate the determination of atmospheric parameters of M-type stars. In this work, we present an empirical sample of 5105 M-type star spectra with homogeneous atmospheric parameter labels through stellar-…
Mass-loss Rate of Highly Evolved Stars in the Magellanic Clouds
Yang, Ming; Gao, Jian; Ren, Yi +3 more
Asymptotic giant branch stars (AGBs) and red supergiant stars (RSGs) exhibit significant mass-loss phenomena and are considered important sources of interstellar dust. In this work, we employed a uniform method of spectral energy distribution fitting to analyze a large, and hence statistically significant, sample of approximately 40,000 RSGs and A…