Search Publications
The Epoch of Giant Planet Migration Planet Search Program. II. A Young Hot Jupiter Candidate around the AB Dor Member HS Psc
Cochran, William D.; Mahadevan, Suvrath; Tran, Quang H. +6 more
We report the discovery of a hot Jupiter candidate orbiting HS Psc, a K7 (≈0.7 M ⊙) member of the ≈130 Myr AB Doradus moving group. Using radial velocities over 4 yr from the Habitable-zone Planet Finder spectrograph at the Hobby–Eberly Telescope, we find a periodic signal of ${P}_{b}={3.986}_{-0.003}^{+0.044}$ days. A joint Keplerian a…
Deep Search for a Scattered Light Dust Halo Around Vega with the Hubble Space Telescope
Wolff, Schuyler G.; Wilner, David J.; Rieke, George H. +6 more
We present a provisory scattered-light detection of the Vega debris disk using deep Hubble Space Telescope (HST) coronagraphy (PID 16666). At only 7.7 pc, Vega is immensely important in debris disk studies both for its prominence and also because it allows the highest physical resolution among all debris systems relative to temperature zones aroun…
Moving Groups in the Solar Neighborhood with Gaia, APOGEE, GALAH, and LAMOST: Dynamical Effects Gather Gas and the Ensuing Star Formation Plays an Important Role in Shaping the Stellar Velocity Distributions
Zhao, Jingkun; Yoon, Suk-Jin; Liang, Xilong
With Gaia, APOGEE, GALAH, and LAMOST data, we investigate the positional, kinematic, chemical, and age properties of nine moving groups in the solar neighborhood. We find that each moving group has a distinct distribution in the velocity space in terms of its metallicity, α abundance, and age. Comparison of the moving groups with their underlying …
UOCS XIV: Study of the Open Cluster NGC 2627 Using UVIT/AstroSat
Panthi, Anju; Vaidya, Kaushar; Saketh, Pinapati
We study the intermediate-age open cluster NGC 2627, located at a distance of ∼2 kpc, using UVIT/AstroSat and other archival data. Using a machine learning-based algorithm, ML-MOC, on the Gaia DR3 data, we identify 422 cluster members, including four blue straggler stars (BSSs), one yellow straggler star (YSS), one blue lurker (BL), one red clump …
Fast and Robust Noise Background Modeling and Quasiperiodic Oscillation Detection for Astronomical Time Series
Xu, Chang
Spectrum with confidence levels is a commonly used method for quasiperiodic oscillation (QPO) detection, but it is prone to yield false positives for two reasons: poor choice and/or biased modeling of the null hypothesis (or noise background). Motivated by this, we propose a new time-domain maximum-likelihood estimation method, which can quickly a…
Characterization of Blue and Yellow Straggler Stars of Berkeley 39
Panthi, Anju; Vaidya, Kaushar; Rao, Khushboo K. +1 more
We characterize blue straggler stars (BSSs) and yellow straggler stars (YSSs) of the open cluster (OC) Berkeley 39 using multiwavelength observations including the Swift/Ultraviolet and Optical Telescope (UVOT). Our analysis also makes use of ultraviolet (UV) data from Galaxy Evolution Explorer, optical data from Gaia DR3 and Panoramic Survey Tele…
Hic Sunt Dracones: Uncovering Dynamical Perturbers within the Habitable Zone
Kane, Stephen R.; Burt, Jennifer A.
The continuing exploration of neighboring planetary systems is providing deeper insights into the relative prevalence of various system architectures, particularly with respect to the solar system. However, a full assessment of the dynamical feasibility of possible terrestrial planets within the habitable zones (HZs) of nearby stars requires detai…
The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER). VI. The High-mass Stellar Initial Mass Function of M33
Bell, Eric F.; Skillman, Evan D.; Lindberg, Christina W. +15 more
We measure the high-mass stellar initial mass function (IMF) from resolved stars in M33 young stellar clusters. Leveraging the Hubble Space Telescope's high resolving power, we fully model the IMF probabilistically. We first model the optical color–magnitude diagram of each cluster to constrain its power-law slope Γ, marginalized over other cluste…
Confirming the Warm and Dense Sub-Saturn TIC 139270665 b with the Automated Planet Finder and Unistellar Citizen Science Network
Gagliano, Robert; Kristiansen, Martti H.; LaCourse, Daryll M. +60 more
We report the discovery and confirmation of the Transiting Exoplanet Survey Satellite (TESS) single-transit, warm and dense sub-Saturn, TIC 139270665 b. This planet is unusually dense for its size: with a bulk density of 2.13 g cm‑3 (0.645R J , 0.463M J ), it is the densest warm sub-Saturn of the TESS family. It …
Extinction of Taurus, Orion, Perseus and California Molecular Clouds Based on the LAMOST, 2MASS, and Gaia Surveys. II. The Extinction Law
Wang, Shu; Jiang, Biwei; Li, Jun +1 more
The extinction law from ultraviolet (UV) to infrared (IR; 0.2–24 µm) is determined by relying on the blue-edge method and color-excess ratios for some nearby molecular clouds, from the low-mass star-forming region to the massive star-forming region. The observational data are collected from nine photometric surveys, along with stellar parame…