K2-139 b: a low-mass warm Jupiter on a 29-d orbit transiting an active K0 V star
Journal article, 2018

We announce the discovery of K2-139 b (EPIC 218916923 b), a transiting warm-Jupiter (Teq = 547 ± 25 K) on a 29-d orbit around an active (log R'_HK = -4.46 ± 0.06) K0V star in K2 Campaign 7. We derive the system's parameters by combining the K2 photometry with ground-based follow-up observations. With a mass of 0.387_-0.075^+0.083 M_J and radius of 0.808_-0.033^+0.034 R_J, K2-139 b is one of the transiting warm Jupiters with the lowest mass known to date. The planetary mean density of 0.91_-0.20^+0.24 g/cm^3 can be explained with a core of ~50 M⊕. Given the brightness of the host star (V = 11.653 mag), the relatively short transit duration (~5 h), and the expected amplitude of the Rossiter-McLaughlin effect (~25m/s), K2-139 is an ideal target to measure the spin-orbit angle of a planetary system hosting a warm Jupiter.

planets and satellites: detection

stars: fundamental parameters

planets and satellites: individual: K2-139 b (EPIC 218916923b)

planetary systems

Author

O. Barragán

University of Turin

D. Gandolfi

University of Turin

A. M. S. Smith

German Aerospace Center (DLR)

H. J. Deeg

University of La Laguna

Malcolm Fridlund

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Carina Persson

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

P. Donati

Istituto nazionale di astrofisica (INAF)

M. Endl

The University of Texas at Austin

Sz. Csizmadia

German Aerospace Center (DLR)

S. Grziwa

University of Cologne

D. Nespral

University of La Laguna

Artie P. Hatzes

Thüringer Landessternwarte Tautenburg

W. D. Cochran

The University of Texas at Austin

L. Fossati

Austrian Academy of Sciences

S. S. Brems

Heidelberg University

J. Cabrera

German Aerospace Center (DLR)

F. Cusano

Istituto nazionale di astrofisica (INAF)

Ph. Eigmüller

University of Turin

C. Eiroa

Universidad Autonoma de Madrid (UAM)

A. Erikson

German Aerospace Center (DLR)

E. W. Guenther

Thüringer Landessternwarte Tautenburg

J. Korth

University of Cologne

D. Lorenzo-Oliveira

University of Sao Paulo (USP)

L. Mancini

Max-Planck Institute for Radio Astronomy

Istituto nazionale di astrofisica (INAF)

University of Rome Tor Vergata

M. Pätzold

University of Cologne

J. Prieto-Arranz

University of La Laguna

H. Rauer

German Aerospace Center (DLR)

Technische Universität Berlin

I. Rebollido

Universidad Autonoma de Madrid (UAM)

J. Saario

Nordic Optical Telescope

O. V. Zakhozhay

National Academy of Sciences in Ukraine

Max-Planck Institute for Radio Astronomy

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 475 2 1765-1776

Exoplanets 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

DOI

10.1093/mnras/stx3207

More information

Latest update

9/15/2023