The SOPHIE search for northern extrasolar planets
VI. Three new hot Jupiters in multi-planet extrasolar systems
C. Moutou, G. Hébrard, F. Bouchy, L. Arnold, N. C. Santos, N. Astudillo, I. Boisse, X. Bonfils, S. Borgniet, X. Delfosse, R. F. Díaz, D. Ehrenreich, T. Forveille, J. Gregorio, O. Labrevoir, A.-M. Lagrange, G. Montagnier, M. Montalto, F. Pepe, J. Sahlmann, A. Santerne, D. Ségransan, S. Udry, M. Vanhuysse
We present high-precision radial-velocity measurements of three solar-type stars: HD13908, HD159243, and HIP 91258. The observations were made with the SOPHIE spectrograph at the 1.93-m telescope of Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanetary systems composed of at least two companions. HD13908 b is a planet with a minimum mass of 0.865±0.035 MJup on a circular orbit with a period of 19.382±0.006 days. There is an outer massive companion in the system with a period of 931±17 days, e = 0.12±0.02, and a minimum mass of 5.13±0.25 MJup. The star HD159243 also has two detected companions with respective masses, periods, and eccentricities of Mp = 1.13±0.05 and 1.9±0.13MJup, P = 12.620±0.004 and 248.4±4.9 days, and e = 0.02±0.02 and 0.075±0.05. Finally, the star HIP 91258 has a planetary companion with a minimum mass of 1.068±0.038 MJup, an orbital period of 5.0505±0.0015 days, and a quadratic trend indicating an outer planetary or stellar companion that is as yet uncharacterized. The planet-hosting stars HD13908, HD159243, and HIP 91258 are main-sequence stars of spectral types F8V, G0V, and G5V, respectively, with moderate activity levels. HIP 91258 is slightly over-metallic, while the two other stars have solar-like metallicity. The three systems are discussed in the frame of formation and dynamical evolution models of systems composed of several giant planets.
Planetary systems – Techniques: radial velocities – Techniques: photometry – Stars: individual: HD13908, HD159243, HIP 91258
Astronomy and Astrophysics
Volume 563, Página A22_1
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