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

TL;DR

This paper reports the detection of a long-period Jovian planet orbiting GJ 777 A using radial-velocity measurements, highlighting the challenges of constraining orbital parameters due to signal amplitude.

Contribution

First detection of a Jovian planet around GJ 777 A using radial-velocity data, demonstrating the capability to find long-period exoplanets around nearby stars.

Findings

Detected a Jovian planet with a 10.7-year orbit

Minimum mass of the planet is 1.33 Jupiter masses

Orbital eccentricity is approximately 0.48

Abstract

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.