Search Publications
Rotation of Low-mass Stars in Upper Centaurus-Lupus and Lower Centaurus-Crux with TESS
Powell, Brian P.; Kruse, Ethan; Rebull, L. M. +3 more
We present stellar rotation rates derived from Transiting Exoplanet Survey Satellite (TESS) light curves for stars in Upper Centaurus-Lupus (UCL; ~136 pc, ~16 Myr) and Lower Centaurus-Crux (LCC; ~115 pc, ~17 Myr). We find spot-modulated periods (P) for ~90% of members. The range of light-curve and periodogram shapes echoes that found for other clu…
A Census of Stars and Disks in Corona Australis
Luhman, K. L.; Esplin, T. L.
We have performed a census of the young stellar populations near the Corona Australis molecular cloud using photometric and kinematic data from several sources, particularly Gaia EDR3, and spectroscopy of hundreds of candidate members. We have compiled a catalog of 393 members of Corona Australis, (39 at >M6), 293 (36) of which are spectroscopi…
Transit Hunt for Young and Maturing Exoplanets (THYME). VIII. A Pleiades-age Association Harboring Two Transiting Planetary Systems from Kepler
Vanderburg, Andrew; Kraus, Adam L.; Barber, Madyson G. +8 more
Young planets provide a window into the early stages and evolution of planetary systems. Ideal planets for such research are in coeval associations, where the parent population can precisely determine their ages. We describe a young association (MELANGE-3) in the Kepler field, which harbors two transiting planetary systems (KOI-3876 and Kepler-970…
A Zwicky Transient Facility Look at Optical Variability of Young Stellar Objects in the North America and Pelican Nebulae Complex
Hillenbrand, Lynne A.; Rebull, Luisa M.; Kuhn, Michael A. +4 more
We present a study of 323 photometrically variable young stellar objects that are likely members of the North America and Pelican nebulae star-forming region. To do so, we utilize over two years of data in the g and r photometric bands from the Zwicky Transient Facility. We first investigate periodic variability, finding 46 objects (~15% of the sa…
Revisiting WASP-47 with ESPRESSO and TESS
Bayliss, Daniel; Bryant, Edward M.
WASP-47 hosts a remarkable planetary system containing a hot Jupiter (WASP-47 b; P = 4.159 days) with an inner super-Earth (WASP-47 e; P = 0.7896 days), a close-orbiting outer Neptune (WASP-47 d; P = 9.031 days), and a long-period giant planet (WASP-47 c; P = 588.4 days). We use the new Transiting Exoplanet Survey Satellite (TESS) photometry to re…
SKYSURF: Constraints on Zodiacal Light and Extragalactic Background Light through Panchromatic HST All-sky Surface-brightness Measurements. I. Survey Overview and Methods
Pirzkal, Nor; Casertano, Stefano; Driver, Simon P. +35 more
We give an overview and describe the rationale, methods, and testing of the Hubble Space Telescope (HST) Archival Legacy project "SKYSURF." SKYSURF uses HST's unique capability as an absolute photometer to measure the ~0.2-1.7 µm sky-surface brightness (sky-SB) from 249,861 WFPC2, ACS, and WFC3 exposures in ~1400 independent HST fields. SKYS…
The Transmission Spectrum of WASP-17 b From the Optical to the Near-infrared Wavelengths: Combining STIS, WFC3, and IRAC Data Sets
Changeat, Quentin; Edwards, Billy; Morvan, Mario +6 more
We present the transmission spectrum of the inflated hot Jupiter WASP-17 b, observed with the STIS and WFC3 instruments aboard the Hubble Space Telescope, allowing for a continuous wavelength coverage from ~0.4 to ~1.7 µm. Observations taken with IRAC channels 1 and 2 on the Spitzer Space Telescope are also included, adding photometric measu…
More Evidence for Variable Helium Absorption from HD 189733b
Redfield, Seth; Knutson, Heather A.; France, Kevin +5 more
We present a new Keck/NIRSPEC observation of metastable helium absorption from the upper atmosphere of HD 189733b, a hot Jupiter orbiting a nearby moderately active star. We measure an average helium transit depth of 0.420% ± 0.013% integrated over the [-20, 20] km s-1 velocity range. Comparing this measurement to eight previously publi…
A Young, Low-density Stellar Stream in the Milky Way Disk: Theia 456
Kounkel, Marina; Covey, Kevin R.; Agüeros, Marcel A. +4 more
Our view of the variety of stellar structures pervading the local Milky Way has been transformed by the application of clustering algorithms to the Gaia catalog. In particular, several stellar streams have been recently discovered that are comprised of hundreds to thousands of stars and span several hundred parsecs. We analyze one such structure, …
EXPRES. III. Revealing the Stellar Activity Radial Velocity Signature of ϵ Eridani with Photometry and Interferometry
Monnier, John D.; Lanthermann, Cyprien; Anugu, Narsireddy +20 more
The distortions of absorption line profiles caused by photospheric brightness variations on the surfaces of cool, main-sequence stars can mimic or overwhelm radial velocity (RV) shifts due to the presence of exoplanets. The latest generation of precision RV spectrographs aims to detect velocity amplitudes ≲ 10 cm s-1, but requires mitig…