The SOPHIE search for northern extrasolar planets. II. A multi-planet system around HD9446

G. Hebrard; X. Bonfils; D. Segransan; C. Moutou; X. Delfosse; F. Bouchy; I. Boisse; L. Arnold; M. Desort; R. F. Diaz; A. Eggenberger; D. Ehrenreich; T. Forveille; A. -M. Lagrange; C. Lovis; F. Pepe; C. Perrier; F. Pont; D. Queloz; N. C. Santos; S. Udry; A. Vidal-Madjar

doi:10.1051/0004-6361/200913790

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arXiv · 1001.0682

The SOPHIE search for northern extrasolar planets. II. A multi-planet system around HD9446

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Abstract

We report the discovery of a planetary system around HD9446, performed from radial velocity measurements secured with the spectrograph SOPHIE at the 193-cm telescope of the Haute-Provence Observatory during more than two years. At least two planets orbit this G5V, active star: HD9446b has a minimum mass of 0.7 M_Jup and a slightly eccentric orbit with a period of 30 days, whereas HD9446c has a minimum mass of 1.8 M_Jup and a circular orbit with a period of 193 days. As for most of the known multi-planet systems, the HD9446-system presents a hierarchical disposition, with a massive outer planet and a lighter inner planet.

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G. Hebrard, X. Bonfils, D. Segransan, C. Moutou, X. Delfosse, F. Bouchy, I. Boisse, L. Arnold, M. Desort, R. F. Diaz, A. Eggenberger, D. Ehrenreich, T. Forveille, A. -M. Lagrange, C. Lovis, F. Pepe, C. Perrier, F. Pont, D. Queloz, N. C. Santos, S. Udry, A. Vidal-Madjar. 2010-01-05. The SOPHIE search for northern extrasolar planets. II. A multi-planet system around HD9446. https://doi.org/10.1051/0004-6361/200913790

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