학술논문
MASS CONSTRAINTS OF THE WASP-47 PLANETARY SYSTEM FROM RADIAL VELOCITIES
Document Type
article
Author
Sinukoff, Evan; Howard, Andrew W; Petigura, Erik A; Fulton, Benjamin J; Isaacson, Howard; Weiss, Lauren M; Brewer, John M; Hansen, Brad MS; Hirsch, Lea; Christiansen, Jessie L; Crepp, Justin R; Crossfield, Ian JM; Schlieder, Joshua E; Ciardi, David R; Beichman, Charles A; Knutson, Heather A; Benneke, Bjoern; Dressing, Courtney D; Livingston, John H; Deck, Katherine M; Lépine, Sébastien; Rogers, Leslie A
Source
The Astronomical Journal. 153(2)
Subject
Language
Abstract
We report precise radial velocity (RV) measurements of WASP-47, a G star that hosts three transiting planets in close proximity (a hot Jupiter, a super-Earth, and a Neptune-sized planet) and a non-transiting planet at 1.4 au. Through a joint analysis of previously published RVs and our own Keck-HIRES RVs, we significantly improve the planet mass and bulk density measurements. For the super-Earth WASP-47e (P = 0.79 days), we measure a mass of 9.11 ± 1.17 Ṁ, and a bulk density of 7.63 ± 1.90 g cm-3, consistent with a rocky composition. For the hot Jupiter WASP-47b (P = 4.2 days), we measure a mass of 356 ± 12Ṁ(1.12 ± 0.04 MJup) and constrain its eccentricity to at 3σ confidence. For the Neptune-size planet WASP-47d (P = 9.0 days), we measure a mass of 12.75 ± 50.0 and a bulk density of g cm-3, suggesting that it has a thick H/He envelope. For the outer non-transiting planet, we measure a minimum mass of 411 ±18Ṁ(1.29 ± 0.06 MJup), an orbital period of days, and an orbital eccentricity of . Our new measurements are consistent with but two to four times more precise than previous mass measurements.