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 1732393

Subject Categories

Astronomy, Astrophysics and Cosmology

Ocean and River Engineering

Other Physics Topics

DOI

10.1051/0004-6361/201732393

More information

Latest update

11/24/2020