The ELODIE survey for northern extra-solar planets. II. A Jovian planet on a long-period orbit around GJ 777 A

We present radial-velocity measurements obtained with the ELODIE and AFOE spectrographs for GJ 777 A (HD 190360), a metal-rich ([Fe/H] = 0.25) nearby (d = 15.9 pc) star in a stellar binary system. A long-period low radial-velocity amplitude variation is detected revealing the presence of a Jovian planetary companion. Some of the orbital elements remain weakly constrained because of the smallness of the signal compared to our instrumental precision. The detailed orbital shape is therefore not well established. We present our best fitted orbital solution: an eccentric (e = 0.48) 10.7-year orbit. The minimum mass of the companion is 1.33 M_Jup.

Based on observations made with the ELODIE echelle spectrograph mounted on the 1.93-m Telescope at the Observatoire de Haute-Provence (CNRS) and with the AFOE spectrograph mounted on the 1.5-m Telescope at the Fred Lawrence Whipple Observatory (SAO).

The ELODIE and AFOE measurements discussed in this paper are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/410/1051