O. Tamuz, D. Ségransan, S. Udry, M. Mayor, P. Eggenberger, D. Naef, F. Pepe, D. Queloz, N. C. Santos, B.-O. Demory, P. Figuera, M. Marmier, G. Montagnier
We report the detection of two very eccentric planets orbiting HD 4113 and HD 156846 with the CORALIE Echelle spectrograph mounted on the 1.2-m Euler Swiss telescope at La Silla. The first planet, HD 4113 b, has minimum mass of msin i = 1:6 0:2 MJup, a period of P = 526:59 0:21 days and an eccentricity of e = 0:903 0:02. It orbits a metal rich G5V star at a = 1:28AU which displays an additional radial velocity drift of 28 ms^1/yr observed during 8 years. The combination of the radial-velocity data and the non-detection of any main sequence stellar companion in our high contrast images taken at the VLT with NACO/SDI, characterizes the companion as a probable brown dwarf or as a faint white dwarf. The second planet, HD 156846 b, has minimum mass of msin i = 10:45 0:05 MJup, a period of P = 359:51 0:09 days, an eccentricity of e = 0:847 0:002 and is located at a = 1:0 AU from its parent star. HD156846 is a metal rich G0 dwarf and is also the primary of a wide binary system (a > 250AU, P > 4000 years). Its stellar companion, IDS 17147-1914 B , is a M4 dwarf. The very high eccentricities of both planets can be explained by Kozai oscillations induced by the presence of a third object.
Astronomy & Astrophysics
Volume 480, Page L33