Details

Autor(en) / Beteiligte

• Damasso, M
• Biazzo, K
• Bonomo, A S
• Desidera, S
• Lanza, A F
• Nascimbeni, V
• Esposito, M
• Scandariato, G
• Sozzetti, A
• Cosentino, R

Titel

The GAPS programme with HARPS-N at TNG: V. A comprehensive analysis of the XO-2 stellar and planetary systems

Ist Teil von

• Astronomy and astrophysics (Berlin), 2015-03, Vol.575, p.A111

Erscheinungsjahr

2015

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• XO-2 is the first confirmed wide stellar binary system where the almost twin components XO-2N and XO-2S have planets, and it is a peculiar laboratory in which to investigate the diversity of planetary systems. This stimulated a detailed characterization study of the stellar and planetary components based on new observations. We collected high-resolution spectra with the HARPS-N spectrograph and multi-band light curves. Spectral analysis led to an accurate determination of the stellar atmospheric parameters and characterization of the stellar activity, and high-precision radial velocities of XO-2N were measured. We collected 14 transit light curves of XO-2Nb used to improve the transit parameters. Photometry provided accurate magnitude differences between the stars and a measure of their rotation periods. The iron abundance of XO-2N was found to be +0.054 dex greater, within more than 3[sigma], than that of XO-2S. The existence of a long-term variation in the radial velocities of XO-2N is confirmed, and we detected a turnover with respect to previous measurements.