The SOPHIE search for northern extrasolar planets III. A Jupiter-mass companion around HD 109246

TL;DR

This paper reports the discovery of a Jupiter-mass exoplanet orbiting HD 109246 using the SOPHIE spectrograph, introduces a correction method for seeing effects on radial velocities, and details calibration procedures for data analysis.

Contribution

It presents the detection of a new Jupiter-mass planet and introduces calibration techniques for SOPHIE spectrograph data analysis.

Findings

Discovery of a Jupiter-mass planet with 0.77 MJup around HD 109246.

Development of a correction method for seeing effects on radial velocities.

Calibration procedures enabling direct derivation of stellar properties from SOPHIE data.

Abstract

We report the detection of a Jupiter-mass planet discovered with the SOPHIE spectrograph mounted on the 1.93-m telescope at the Haute-Provence Observatory. The new planet orbits HD109246, a G0V star slightly more metallic than the Sun. HD109246b has a minimum mass of 0.77 MJup, an orbital period of 68 days, and an eccentricity of 0.12. It is placed in a sparsely populated region of the period distribution of extrasolar planets. We also present a correction method for the so-called seeing effect that affects the SOPHIE radial velocities. We complement this discovery announcement with a description of some calibrations that are implemented in the SOPHIE automatic reduction pipeline. These calibrations allow the derivation of the photon-noise radial velocity uncertainty and some useful stellar properties (vsini, [Fe/H], logR'HK) directly from the SOPHIE data.