Transiting exoplanets from the CoRoT space mission: XXIX. The hot Jupiters CoRoT-30 b and CoRoT-31 b
Journal article, 2020
We report the discovery as well as the orbital and physical characterizations of two new transiting giant exoplanets, CoRoT-30 b and CoRoT-31 b, with the CoRoT space telescope. Methods. We analyzed two complementary data sets: photometric transit light curves measured by CoRoT, and radial velocity curves measured by the HARPS spectrometer. To derive the absolute masses and radii of the planets, we modeled the stars from available magnitudes and spectra. Results. We find that CoRoT-30 b is a warm Jupiter on a close-to-circular 9.06-day orbit around a G3V star with a semi-major axis of about 0.08 AU. It has a radius of 1.01 ± 0.08 RJ, a mass of 2.90 ± 0.22 MJ, and therefore a mean density of 3.45 ± 0.65 g cm-3. The hot Jupiter CoRoT-31 b is on a close-to-circular 4.63-day orbit around a G2 IV star with a semi-major axis of about 0.05 AU. It has a radius of 1.46 ± 0.30 RJ, a mass of 0.84 ± 0.34 MJ, and therefore a mean density of 0.33 ± 0.18 g cm-3. Conclusions. Neither system seems to support the claim that stars hosting planets are more depleted in lithium. The radii of both planets are close to that of Jupiter, but they differ in mass; CoRoT-30 b is ten times denser than CoRoT-31 b. The core of CoRoT-30 b would weigh between 15 and 75 Earth masses, whereas relatively weak constraints favor no core for CoRoT-31 b. In terms of evolution, the characteristics of CoRoT-31 b appear to be compatible with the high-eccentricity migration scenario, which is not the case for CoRoT-30 b. The angular momentum of CoRoT-31 b is currently too low for the planet to evolve toward synchronization of its orbital revolution with stellar rotation, and the planet will slowly spiral-in while its host star becomes a red giant. CoRoT-30 b is not synchronized either: it looses angular momentum owing to stellar winds and is expected reach steady state in about 2 Gyr. CoRoT-30 and 31, as a pair, are a truly remarkable example of diversity in systems with hot Jupiters.
Planetary systems
Stars: fundamental parameters
Stars: individual: CoRoT-31
Stars: individual: CoRoT-30
Author
P. Bordé
University of Bordeaux
R. F. Díaz
University of Geneva
Universidad de Buenos Aires
O. Creevey
Institut d'Astrophysique Spatiale
Observatoire de la Cote d'Azur
C. Damiani
Max Planck Society
Institut d'Astrophysique Spatiale
H. Deeg
Instituto Astrofisico de Canarias
University of La Laguna
P. Klagyivik
University of La Laguna
Instituto Astrofisico de Canarias
G. Wuchterl
Kuffner Observatory
D. Gandolfi
University of Turin
Heidelberg-Königstuhl State Observatory
Malcolm Fridlund
Max Planck Society
Leiden University
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Galactic Astrophysics
F. Bouchy
University of Geneva
Laboratoire d'Astrophysique de Marseille
S. Aigrain
University of Oxford
R. Alonso
University of La Laguna
Instituto Astrofisico de Canarias
J. M. Almenara
University of Geneva
Laboratoire d'Astrophysique de Marseille
A. Baglin
LESIA - Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique
S.C.C. Barros
Laboratoire d'Astrophysique de Marseille
University of Porto
A. S. Bonomo
Istituto nazionale di astrofisica (INAF)
J. Cabrera
German Aerospace Center (DLR)
Szilard Csizmadia
German Aerospace Center (DLR)
M. Deleuil
Laboratoire d'Astrophysique de Marseille
Anders Erikson
German Aerospace Center (DLR)
S. Ferraz-Mello
University of Sao Paulo (USP)
E. W. Guenther
Thüringer Landessternwarte Tautenburg
T. Guillot
Observatoire de la Cote d'Azur
S. Grziwa
University of Cologne
A. Hatzes
Thüringer Landessternwarte Tautenburg
G. Hebrard
Institut d 'Astrophysique de Paris
T. Mazeh
Tel Aviv University
M. Ollivier
Institut d'Astrophysique Spatiale
LESIA - Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique
H. Parviainen
University of Oxford
Martin Pätzold
University of Cologne
H. Rauer
Technische Universität Berlin
German Aerospace Center (DLR)
D. Rouan
LESIA - Laboratoire d'Etudes Spatiales et d'Instrumentation en Astrophysique
A. Santerne
Laboratoire d'Astrophysique de Marseille
J. Schneider
LUTH - Laboratoire de l'Univers et de ses Theories
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 635 1732393Subject Categories
Astronomy, Astrophysics and Cosmology
Ocean and River Engineering
Other Physics Topics
DOI
10.1051/0004-6361/201732393