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 Astrofisico de Canarias

A. Vanderburg

Harvard-Smithsonian Center for Astrophysics

R. Alonso

University of La Laguna

Instituto Astrofisico 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 Astrofisico 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 Astrofisico de Canarias

University of La Laguna

G. Nowak

Instituto Astrofisico de Canarias

University of La Laguna

E. Palle

University of La Laguna

Instituto Astrofisico de Canarias

M. Patzold

University of Cologne

H. Rauer

German Aerospace Center (DLR)

Technische Universität Berlin

P. Montanés Rodríguez

University of La Laguna

Instituto Astrofisico 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- 226

Exoplanets from space – CHEOPS and PLATO, ESA’s next two projects

Swedish National Space Board, 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

More information

Latest update

9/10/2019