The CORALIE survey for southern extrasolar planets

XIV. HD 142022 b: a long-period planetary companion in a wide binary

¹ Observatoire de Genève, 51 ch. des Maillettes, 1290 Sauverny, Switzerland e-mail: Anne.Eggenberger@obs.unige.ch
² European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Santiago 19, Chile
³ Centro de Astronomia e Astrofísica da Universidade de Lisboa, Observatório Astronómico de Lisboa, Tapada da Ajuda, 1349-018 Lisboa, Portugal

Received: 29 June 2005
Accepted: 12 October 2005

Abstract

We report precise Doppler measurements of HD 142022 obtained during the past six years with the CORALIE echelle spectrograph at La Silla Observatory together with a few additional observations made recently with the HARPS echelle spectrograph. Our radial velocities reveal evidence of a planetary companion with an orbital period  days, an eccentricity , and a velocity semiamplitude  m s^-1. The inferred companion minimum mass is and the semimajor axis  ± 0.05 AU. Only one full orbital revolution has been monitored yet, and the periastron passage could not be observed since the star was too low on the horizon. The eccentricity and velocity semiamplitude remain therefore quite uncertain and the orbital solution is preliminary. HD 142022 is a chromospherically inactive K0 dwarf, metal rich relative to the Sun, and is the primary component of a wide binary. HD 142022 b is thus a new “planet in binary” candidate, and its high eccentricity might be due to secular interactions with the distant stellar companion.