Search Publications
The Origin of the Large Magellanic Cloud Globular Cluster NGC 2005
Piatti, Andrés E.; Hirai, Yutaka
The ancient Large Magellanic Cloud (LMC) globular cluster NGC 2005 has recently been reported to have an ex situ origin, thus, setting precedents that the LMC could have partially formed from smaller merged dwarf galaxies. We here provide additional arguments from which we conclude that is also fairly plausible an in situ origin of NGC 2005, based…
A Census of the Most Luminous Stars. I. The Upper HR Diagram for the Large Magellanic Cloud
Humphreys, Roberta M.; Martin, John C.
Spectral classification and multiwavelength photometry for the most luminous stars in the LMC has greatly increased due to several recent surveys for both the hottest and coolest members. Combining data from these spectroscopic and photometric surveys, we have created catalogs based on their spectral classifications of the different groups: the lu…
LAMOST J2043+3413-a Fast Disk Precession SW Sextans Candidate in Period Gap
Wang, Xiaofeng; Liu, Jiren; Sun, Yongkang +5 more
We present follow-up photometric observations and time-series analysis of a nova-like, SW Sextans-type, cataclysmic variable (CV) candidate, LAMOST J204305.95+341340.6 (hereafter J2043+3413), with a Gaia G-band magnitude of 15.30 and a distance of 990 pc, which was identified from the LAMOST spectrum. The photometric data were collected with the T…
KIC 9028474: A Long-period Eclipsing Binary on a Highly Eccentric Orbit
Özdarcan, Orkun
We present a comprehensive analysis of a very long-period (124.93669 days) eclipsing binary KIC 9028474, which is composed of F9V+G1V components on a highly eccentric (e = 0.82029) orbit. Masses and radii of the primary and the secondary components are M 1 = 1.18 ± 0.04 M ⊙, M 2 = 1.04 ± 0.03 M ⊙, R
A Reinforcement Learning-Based Follow-up Framework
Astudillo, Javiera; Protopapas, Pavlos; Pichara, Karim +1 more
Classification and characterization of variable and transient phenomena are critical for astrophysics and cosmology. Given the volume of nightly data produced by ongoing and future surveys such as LSST, it is critical to develop automatic tools that assist in observation decision-making, maximizing scientific output without resource wastage. We pr…
New Insights on 30 Dor B Revealed by High-quality Multiwavelength Observations
Liu, Sheng-Yuan; Chu, You-Hua; Ueda, Shutaro +4 more
The supernova remnant (SNR) 30 Dor B is associated with the H II region ionized by the OB association LH99. The complex interstellar environment has made it difficult to study the physical structure of this SNR. We have used Hubble Space Telescope Hα images to identify SNR shocks and deep Chandra X-ray observations to detect faint diffuse emission…
An Investigation of New Brown Dwarf Spectral Binary Candidates From the Backyard Worlds: Planet 9 Citizen Science Initiative
Meisner, Aaron M.; Kirkpatrick, J. Davy; Burgasser, Adam J. +9 more
We present three new brown dwarf spectral-binary candidates: CWISE J072708.09-360729.2, CWISE J103604.84-514424.4, and CWISE J134446.62-732053.9, discovered by citizen scientists through the Backyard Worlds: Planet 9 project. Follow-up near-infrared spectroscopy shows that each of these objects is poorly fit by a single near-infrared standard. We …
The Kinematics of the Young Stellar Population in the W5 Region of the Cassiopeia OB6 Association: Implication for the Formation Process of Stellar Associations
Lim, Beomdu; Yun, Hyeong-Sik; Park, Byeong-Gon +3 more
The star-forming region W5 is a major part of the Cassiopeia OB6 association. Its internal structure and kinematics may provide hints of the star formation process in this region. Here, we present a kinematic study of young stars in W5 using the Gaia data and our radial velocity data. A total 490 out of 2000 young stars are confirmed as members. T…
A Six Year, Low-resolution, Multibroadband Transit Photometry Study of HD 189733b
Piccone, Ashley N.; Kobulnicky, Henry A.; Jang-Condell, Hannah +13 more
Transmission spectroscopy offers an invaluable opportunity to characterize the atmospheres of exoplanets. We present new ground-based optical transmission spectra of the hot Jupiter HD 189733b, derived from nine transits observed over a six year time span (2016-2021) using near-simultaneous $u^{\prime} g^{\prime} r^{\prime} i^{\prime} $ broadband …
Monitoring Hα Emission from the Wide-orbit Brown-dwarf Companion FU Tau B
Bowler, Brendan P.; Close, Laird M.; Wu, Ya-Lin +5 more
Monitoring mass accretion onto substellar objects provides insights into the geometry of the accretion flows. We use the Lulin One-meter Telescope to monitor Hα emission from FU Tau B, a ~19 M Jup brown-dwarf companion at 5.″7 (719 au) from the host star, for six consecutive nights. This is the longest continuous Hα monitoring for a sub…