Search Publications
Supplement: "An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing" (2022, ApJL, 933, L23)
Lu, Jessica R.; Udalski, Andrzej; Mróz, Przemek +42 more
This supplement provides supporting material for Lam et al. We briefly summarize past gravitational microlensing searches for black holes (BHs) and present details of the observations, analysis, and modeling of five BH candidates observed with both ground-based photometric microlensing surveys and Hubble Space Telescope astrometry and photometry. …
CoSHA: Code for Stellar Properties Heuristic Assignment-for the MaStar Stellar Library
Yan, Renbin; Drory, Niv; Bruzual, Gustavo +5 more
We introduce COSHA: a Code for Stellar properties Heuristic Assignment. In order to estimate the stellar properties, COSHA implements a Gradient Tree Boosting algorithm to label each star across the parameter space (T eff, $\mathrm{log}g$ , [Fe/H], and [α/Fe]). We use COSHA to estimate the stellar atmospheric parameters of 22,000 unique…
LSST Survey Strategies and Brown Dwarf Parallaxes
Gizis, John E.; Yoachim, Peter; Jones, R. Lynne +2 more
The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) has the potential to measure parallaxes for thousands of nearby ultracool dwarfs, enabling improved measurements of the brown dwarf luminosity function. We develop a simple model to estimate the number of L dwarfs and T dwarfs with parallaxes with signal-to-noise ratio greater …
The Second Catalog of Interplanetary Network Localizations of Konus Short-duration Gamma-Ray Bursts
Mitrofanov, I.; Hurley, K.; Yamaoka, K. +72 more
We present the catalog of InterPlanetary Network (IPN) localizations for 199 short-duration gamma-ray bursts (sGRBs) detected by the Konus-Wind (KW) experiment between 2011 January 1 and 2021 August 31, which extends the initial sample of IPN-localized KW sGRBs to 495 events. We present the most comprehensive IPN localization data on these events,…
A Catalog of LAMOST Variable Sources Based on Time-domain Photometry of ZTF
Mei, Ying; Wang, Feng; Deng, Hui +4 more
The identification and analysis of different variable sources is a hot topic in astrophysical research. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic survey has accumulated a mass of spectral data but contains no information about variable sources. Although a few related studies present variable source catalo…
Dwarf Irregular Galaxy Leo A. II. Suprime-Cam R and Hα Stellar Photometry
Stonkutė, Rima; Vansevičius, Vladas
We have surveyed the complete extent of Leo A, which is an apparently isolated Local Group dwarf irregular galaxy, in B, V, R, I (the Johnson-Cousins system), and NA656 (centered on Hα) passbands with the Subaru Telescope equipped with the Suprime-Cam mosaic camera. B, V, and I photometry results were published earlier by Stonkutė et al. The recen…
A Publicly Available Multiobservatory Data Set of an Enhanced Network Patch from the Photosphere to the Corona
Warren, Harry P.; Savage, Sabrina; Kobelski, Adam R. +3 more
New instruments sensitive to chromospheric radiation at X-ray, UV, visible, IR, and submillimeter wavelengths have become available that significantly enhance our ability to understand the bidirectional flow of energy through the chromosphere. We describe the calibration, coalignment, initial results, and public release of a new data set combining…
New Fe I Level Energies and Line Identifications from Stellar Spectra. III. Initial Results from UV, Optical, and Infrared Spectra
Peterson, Ruth C.; Kurucz, Robert L.
The spectrum of neutral iron is critical to astrophysics, yet furnace laboratory experiments cannot reach high-lying Fe I levels. Instead, Peterson & Kurucz and Peterson et al. adopted ultraviolet (UV) and optical spectra of warm stars to identify and assign energies for 124 Fe I levels with 1900 detectable Fe I lines, and to derive astrophysi…
Data-driven Model of Temporal Evolution of Solar Mg II h and k Profiles over the Solar Cycle
Heinzel, Petr; Gunár, Stanislav; Koza, Július +2 more
The solar radiation in the cores of the Mg II h and k spectral lines plays a significant role in the illumination of prominences, coronal mass ejections (CMEs), spicules, flare loops, and surges. Moreover, the radiation in these lines strongly correlates with solar magnetic activity and the ultraviolet solar spectral irradiance affecting the photo…
Selection of the Main Control Parameters for the Dst Index Prediction Model Based on a Layer-wise Relevance Propagation Method
Zhang, J.; Wang, Z.; Li, Y. Y. +8 more
The prediction of the Dst index is an important subject in space weather. It has significant progress with the prevalent applications of neural networks. The selection of input parameters is critical for the prediction model of the Dst index or other space-weather models. In this study, we perform a layer-wise relevance propagation (LRP) method to…