Transiting exoplanets from the CoRoT space mission. XXVI. CoRoT-24: a transiting multiplanet system

Author(s)

Roi Alonso, Claire Moutou, Michael Endl, Rudolf Dvorak

Abstract

We present the discovery of a candidate multiply transiting system, the first one found in the CoRoT mission. Two transit-like features with periods of 5.11 and 11.76 d are detected in the CoRoT light curve around a main sequence K1V star of r = 15.1. If the features are due to transiting planets around the same star, these would correspond to objects of 3.7 ± 0.4 and 5.0 ± 0.5 R, respectively. Several radial velocities serve to provide an upper limit of 5.7 M for the 5.11 d signal and to tentatively measure a mass of 28

⁺¹¹

_-11 M for the object transiting with a 11.76 d period. These measurements imply low density objects, with a significant gaseous envelope. The detailed analysis of the photometric and spectroscopic data serves to estimate the probability that the observations are caused by transiting Neptune-sized planets as much as over 26 times higher than a blend scenario involving only one transiting planet and as much as over 900 times higher than a scenario involving two blends and no planets. The radial velocities show a long-term modulation that might be attributed to a 1.5 M

_Jup planet orbiting at 1.8 AU from the host, but more data are required to determine the precise orbital parameters of this companion.

Organisation(s)

Department of Astrophysics

External organisation(s)

Université de Genève, Université de Provence Aix-Marseille I, University of Texas, Austin

Journal

Astronomy & Astrophysics

Volume

567

No. of pages

13

ISSN

0004-6361

DOI

https://doi.org/10.1051/0004-6361/201118662

Publication date

07-2014

Peer reviewed

Yes

Austrian Fields of Science 2012

103003 Astronomy, 103004 Astrophysics

Keywords

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/0be4aa56-5403-400d-b57e-f897f9e58042