The Discovery and Mass Measurement of a New Ultra-short-period Planet: K2-131
Journal article, 2017
We report the discovery of a new ultra-short-period planet and summarize the properties of all such planets for which the mass and radius have been measured. The new planet, EPIC 228732031b, was discovered in K2 Campaign 10. It has a radius of 1.81-0.12+0.16 R_Earth and orbits a G dwarf with a period of 8.9 hr. Radial velocities obtained with Magellan/PFS and TNG/HARPS-N show evidence for stellar activity along with orbital motion. We determined the planetary mass using two different methods: (1) the “floating chunk offset” method, based only on changes in velocity observed on the same night; and (2) a Gaussian process regression based on both the radial velocity and photometric time series. The results are consistent and lead to a mass measurement of 6.5+/- 1.6 M_Earth and a mean density of 6.0-2.7+3.0 g cm‑3.
planetary systems
stars: individual: EPIC 228732031
Author
F. Dai
Princeton University
Massachusetts Institute of Technology (MIT)
N. Joshua
Princeton University
D. Gandolfi
University of Turin
S. Wangm
Carnegie Institution of Washington
J.K. Teske
Carnegie Observatories
J. Burt
Massachusetts Institute of Technology (MIT)
S. Albrecht
Aarhus University
O. Barragán
University of Turin
William D. Cochran
The University of Texas at Austin
M. Endl
The University of Texas at Austin
Malcolm Fridlund
Astronomy and Plasmaphysics
Artie P. Hatzes
Thüringer Landessternwarte Tautenburg
T. Hirano
Tokyo Institute of Technology
L.A. Hirsch
University of California
M.C. Johnson
Ohio State University
A.B. Justesen
Aarhus University
J. Livingston
University of Tokyo
Carina Persson
Astronomy and Plasmaphysics
J. Prieto-Arranz
University of La Laguna
Instituto de Astrofísica de Canarias
A. Vanderburg
Harvard-Smithsonian Center for Astrophysics
R. Alonso
University of La Laguna
Instituto de Astrofísica de Canarias
G. Antoniciello
University of Turin
P. Arriagada
Carnegie Institution of Washington
R.P. Butler
Carnegie Institution of Washington
J. Cabrera
German Aerospace Center (DLR)
J.D. Crane
Carnegie Observatories
F. Cusano
Osservatorio Astronomico Di Bologna
S. Csizmadia
German Aerospace Center (DLR)
H. Deeg
University of La Laguna
Instituto de Astrofísica de Canarias
S.B. Dieterich
Carnegie Institution of Washington
P. Eigmüller
German Aerospace Center (DLR)
A. Erikson
German Aerospace Center (DLR)
M.E. Everett
National Optical Astronomy Observatory
Fukui A.
National Astronomical Observatory of Japan
S. Grziwa
University of Cologne
E. W. Guenther
Thüringer Landessternwarte Tautenburg
G.W. Henry
Tennessee State University
S.B. Howell
NASA Ames Research Center
J.A. Johnson
Harvard-Smithsonian Center for Astrophysics
J. Korth
University of Cologne
M. Kuzuhara
National Astronomical Observatory of Japan
National Institutes of Natural Sciences
N. Narita
National Astronomical Observatory of Japan
University of Tokyo
National Institutes of Natural Sciences
D. Nespral
Instituto de Astrofísica de Canarias
University of La Laguna
G. Nowak
Instituto de Astrofísica de Canarias
University of La Laguna
E. Palle
University of La Laguna
Instituto de Astrofísica de Canarias
M. Patzold
University of Cologne
H. Rauer
German Aerospace Center (DLR)
Technische Universität Berlin
P. Montanés Rodríguez
University of La Laguna
Instituto de Astrofísica de Canarias
S.A. Shectman
Carnegie Observatories
A. M S Smith
German Aerospace Center (DLR)
I.B. Thompson
Carnegie Observatories
V. Van Eylen
Leiden University
M.W. Williamson
Tennessee State University
R.A. Wittenmyer
University of Southern Queensland
Astronomical Journal
0004-6256 (ISSN) 1538-3881 (eISSN)
Vol. 154 6 226- 226Exoplanets from space – CHEOPS and PLATO, ESA’s next two projects
Swedish National Space Board (174/18), 2017-01-01 -- 2022-12-31.
Subject Categories
Astronomy, Astrophysics and Cosmology
Roots
Basic sciences
Infrastructure
Onsala Space Observatory
DOI
10.3847/1538-3881/aa9065