The CORALIE survey for southern extra-solar planets

Abstract

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 , a period of days and an eccentricity of . It orbits a metal rich G5V star at AU, which displays an additional radial velocity drift of 28 m s-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 , a period of days, an eccentricity of and is located at AU from its parent star. HD 156846 is a metal rich G0 dwarf and is also the primary of a wide binary system (250$]]> AU, 4000$]]> 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. © 2008 ESO.