Search Publications
Four Sub-Saturns with Dissimilar Densities: Windows into Planetary Cores and Envelopes
Schlieder, Joshua E.; Howell, Steve B.; Fulton, Benjamin J. +12 more
We present results from a Keck/HIRES radial velocity campaign to study four sub-Saturn-sized planets, K2-27b, K2-32b, K2-39b, and K2-108b, with the goal of understanding their masses, orbits, and heavy-element enrichment. The planets have similar sizes ({R}{{P}} = 4.5-5.5 {R}\oplus ), but have dissimilar masses ({M}{{P
KELT-20b: A Giant Planet with a Period of P ∼ 3.5 days Transiting the V ∼ 7.6 Early A Star HD 185603
Bieryla, Allyson; Latham, David W.; Quinn, Samuel N. +54 more
We report the discovery of KELT-20b, a hot Jupiter transiting a V∼ 7.6 early A star, HD 185603, with an orbital period of P≃ 3.47 days. Archival and follow-up photometry, Gaia parallax, radial velocities, Doppler tomography, and AO imaging were used to confirm the planetary nature of KELT-20b and characterize the system. From global modeling we in…
Zodiacal Exoplanets in Time (ZEIT). V. A Uniform Search for Transiting Planets in Young Clusters Observed by K2
Vanderburg, Andrew; Rizzuto, Aaron C.; Kraus, Adam L. +2 more
Detection of transiting exoplanets around young stars is more difficult than for older systems owing to increased stellar variability. Nine young open cluster planets have been found in the K2 data, but no single analysis pipeline identified all planets. We have developed a transit search pipeline for young stars that uses a transit-shaped notch a…
A Physical Model-based Correction for Charge Traps in the Hubble Space Telescope’s Wide Field Camera 3 Near-IR Detector and Its Applications to Transiting Exoplanets and Brown Dwarfs
Schneider, Glenn; Apai, Dániel; Zhou, Yifan +1 more
The Hubble Space Telescope Wide Field Camera 3 (WFC3) near-IR channel is extensively used in time-resolved observations, especially for transiting exoplanet spectroscopy as well as brown dwarf and directly imaged exoplanet rotational phase mapping. The ramp effect is the dominant source of systematics in the WFC3 for time-resolved observations, wh…
Three’s Company: An Additional Non-transiting Super-Earth in the Bright HD 3167 System, and Masses for All Three Planets
Henning, Thomas; Butler, R. Paul; Vogt, Steven S. +55 more
HD 3167 is a bright (V = 8.9), nearby K0 star observed by the NASA K2 mission (EPIC 220383386), hosting two small, short-period transiting planets. Here we present the results of a multi-site, multi-instrument radial-velocity campaign to characterize the HD 3167 system. The masses of the transiting planets are 5.02 ± 0.38 {M}\oplus for…
Exploring Dust around HD 142527 down to 0.″025 (4 au) Using SPHERE/ZIMPOL
Ménard, F.; Quanz, S. P.; Avenhaus, H. +25 more
We have observed the protoplanetary disk of the well-known young Herbig star HD 142527 using ZIMPOL polarimetric differential imaging with the very broad band (∼600-900 nm) filter. We obtained two data sets in 2015 May and 2016 March. Our data allow us to explore dust scattering around the star down to a radius of ∼0.″025 (∼4 au). The well-known o…
Standard Galactic Field RR Lyrae. I. Optical to Mid-infrared Phased Photometry
Kollmeier, Juna A.; Madore, Barry F.; Freedman, Wendy L. +6 more
We present a multi-wavelength compilation of new and previously published photometry for 55 Galactic field RR Lyrae variables. Individual studies, spanning a time baseline of up to 30 years, are self-consistently phased to produce light curves in 10 photometric bands covering the wavelength range from 0.4 to 4.5 microns. Data smoothing via the GLO…
Orbiting Clouds of Material at the Keplerian Co-rotation Radius of Rapidly Rotating Low-mass WTTs in Upper Sco
Pinsonneault, Marc; Cody, Ann Marie; Rebull, Luisa +8 more
Using K2 data, we identified 23 very-low-mass members of the ρ Oph and Upper Scorpius star-forming region as having periodic photometric variability not easily explained by well-established physical mechanisms such as star spots, eclipsing binaries, or pulsation. All of these unusual stars are mid-to-late M dwarfs without evidence of active accret…
An Optical/Near-infrared Investigation of HD 100546 b with the Gemini Planet Imager and MagAO
Esposito, Thomas M.; Oppenheimer, Rebecca; Wolff, Schuyler G. +52 more
We present H band spectroscopic and Hα photometric observations of HD 100546 obtained with the Gemini Planet Imager and the Magellan Visible AO camera. We detect H band emission at the location of the protoplanet HD 100546 b, but show that the choice of data processing parameters strongly affects the morphology of this source. It appears point-lik…
A Measurement of Radius Inflation in the Pleiades and Its Relation to Rotation and Lithium Depletion
Stassun, Keivan G.; Somers, Garrett
Precise measurements of eclipsing binary parameters and statistical studies of young clusters have suggested that some magnetically active low-mass dwarfs possess radii inflated by ∼5%-15% relative to theoretical expectations. If true, this effect should be pronounced in young open clusters, due to the rapid rotation and strong magnetic activity o…