Search Publications
High-resolution Chemical Abundances of the Nyx Stream
Ji, Alexander P.; Lisanti, Mariangela; Necib, Lina +5 more
Nyx is a nearby, prograde, and high-eccentricity stellar stream physically contained in the thick disk, but its origin is unknown. Nyx could be the remnant of a disrupted dwarf galaxy, in which case the associated dark matter substructure could affect terrestrial dark matter direct-detection experiments. Alternatively, Nyx could be a signature of …
The Structure of Coronal Mass Ejections Recorded by the K-Coronagraph at Mauna Loa Solar Observatory
Chen, Yao; Xia, Lidong; Li, Leping +3 more
Previous survey studies reported that coronal mass ejections (CMEs) can exhibit various structures in white-light coronagraphs, and ~30% of them have the typical three-part feature in the high corona (e.g., 2-6 R ⊙), which has been taken as the prototypical structure of CMEs. It is widely accepted that CMEs result from eruption of magne…
The Ultraviolet to Mid-infrared Extinction Law of the Taurus Molecular Cloud Based on the Gaia DR3, GALEX, APASS, Pan-STARRS1, 2MASS, and WISE Surveys
Wang, Shu; Chen, Xiaodian; Li, Ling +1 more
Interstellar-dust extinction law is essential for interpreting observations. In this work, we investigate the ultraviolet (UV)-mid-infrared (IR) extinction law of the Taurus molecular cloud and its possible variations. We select 504,988 dwarf stars (4200 K ≤ T eff ≤ 8000 K) and 4757 giant stars (4200 K ≤ T eff ≤ 5200 K) based…
Solar Orbiter and SDO Observations, and a Bifrost Magnetohydrodynamic Simulation of Small-scale Coronal Jets
Tiwari, Sanjiv K.; Cheung, Mark C. M.; Berghmans, David +3 more
We report high-resolution, high-cadence observations of five small-scale coronal jets in an on-disk quiet Sun region observed with Solar Orbiter's EUI/HRIEUV in 174 Å. We combine the HRIEUV images with the EUV images of SDO/AIA and investigate the magnetic setting of the jets using coaligned line-of-sight magnetograms from SD…
PEARLS: JWST Counterparts of Microjansky Radio Sources in the Time Domain Field
Grogin, Norman A.; Koekemoer, Anton M.; Pirzkal, Nor +38 more
The Time Domain Field (TDF) near the North Ecliptic Pole in JWST's continuous-viewing zone will become a premier "blank field" for extragalactic science. JWST/NIRCam data in a 16 arcmin2 portion of the TDF identify 4.4 µm counterparts for 62 of 63 3 GHz sources with S(3 GHz) > 5 µJy. The one unidentified radio source may …
New Insights in the Bubble Wall of NGC 3324: Intertwined Substructures and a Bipolar Morphology Uncovered by JWST
Dewangan, L. K.; Sharma, Saurabh; Mayya, Y. D. +4 more
We report the discovery of intertwined/entangled substructures toward the bubble wall of NGC 3324 below a physical scale of 4500 au, which is the sharp edge/ionization front/elongated structure traced at the interface between the H II region and the molecular cloud. The sharp edge appears wavy in the Spitzer 3.6-8.0 µm images (resolution ~2″…
Search for X-Ray Quasiperiodicity of Six AGNs Using the Gaussian Process Method
Zhang, Haoyang; Yang, Shenbang; Dai, Benzhong
The quasiperiodic oscillations (QPOs) found in active galactic nuclei (AGNs) are a very interesting observational phenomenon implying an unknown physical mechanism around supermassive black holes. Several AGNs have been found to have QPO phenomena in the X-ray energy band. Long-duration X-ray observations were collected and reduced for six AGNs wi…
The IGRINS YSO Survey. III. Stellar Parameters of Pre-main-sequence Stars in Ophiuchus and Upper Scorpius
Johns-Krull, Christopher M.; Lee, Jae-Joon; Prato, L. +9 more
We used the Immersion GRating Infrared Spectrometer (IGRINS) to determine fundamental parameters for 61 K- and M-type young stellar objects (YSOs) located in the Ophiuchus and Upper Scorpius star-forming regions. We employed synthetic spectra and a Markov chain Monte Carlo approach to fit specific K-band spectral regions and determine the photosph…
Calibrating X-Ray Binary Luminosity Functions via Optical Reconnaissance. II. The High-mass XLF and Globular Cluster Population of X-Ray Binaries in the Low Star-forming Spiral M81
Chandar, Rupali; Mok, Angus; Gallo, Elena +2 more
We characterize the optical counterparts to the compact X-ray source population within the nearby spiral galaxy M81 using multiband Hubble Space Telescope (HST) imaging data. By comparing the optical luminosities and colors measured for candidate donor stars and host clusters to stellar and cluster evolutionary models, respectively, we estimate th…
The Baryonic Content of Galaxies Mapped by MaNGA and the Gas Around Them
Bershady, Matthew A.; Wake, David A.; Lundgren, Britt +4 more
We analyze the cool gas in and around 14 nearby galaxies (at z < 0.1) mapped with the Sloan Digital Sky Survey IV MaNGA survey by measuring absorption lines produced by gas in spectra of background quasars/active galactic nuclei at impact parameters of 0-25 effective radii from the galactic centers. Using Hubble Space Telescope/Cosmic Origins S…