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Centro de Astrofísica da Universidade do Porto

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

G. Hébrard, X. Bonfils, D. Ségransan, C. Moutou, X. Delfosse, F. Bouchy, I. Boisse, L. Arnold, M. Desort, R. F. Díaz, 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

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 MJup and a slightly eccentric orbit with a period of 30 days, whereas HD9446c has a minimum mass of 1.8 MJup and a circular orbit with a period of 193 days. As for most of the known multi-planet systems, the HD 9446-system presents a hierarchical disposition, with a massive outer planet and a lighter inner planet.

planetary systems – techniques: radial velocities – stars: individual: HD9446

Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (program 07A.PNP.CONS). The full version of Table 1 (SOPHIE measurements of HD9446) is only available in electronic form at the CDS via anonymous ftp to ( or via

Astronomy and Astrophysics
Volume 513, Page A69_1
April 2010

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