The HARPS search for southern extra-solar planets

XXXVII. Five new long-period giant planets and a system update^⋆,⋆⋆

¹ Canada France Hawaii Telescope Corporation, Kamuela 96743, USA
e-mail: moutou@cfht.hawaii.edu
² Aix Marseille Université, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, Marseille, France
³ ESO, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago de Chile, Chile
⁴ Observatoire de Genève, Université de Genève, 51 chemin des Maillettes, 1290 Sauverny, Switzerland
⁵ Physikalisches Institut Universität Bern, Sidlerstrasse 5, 3012 Bern, Switzerland
⁶ Instituto de Astrofísica e Ciências do Espaco, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal
⁷ Centro de Astrofísica e Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal

Received: 12 September 2014
Accepted: 9 December 2014

Abstract

We describe radial-velocity time series obtained by HARPS on the 3.60 m telescope in La Silla (ESO, Chile) over ten years and report the discovery of five new giant exoplanets in distant orbits; these new planets orbit the stars HD 564, HD 30669, HD 108341, and BD -114672. Their periods range from 492 to 1684 days, semi-major axes range from 1.2 to 2.69 AU, and eccentricities range from 0 to 0.85. Their minimum mass ranges from 0.33 to 3.5 M_Jup. We also refine the parameters of two planets announced previously around HD 113538, based on a longer series of measurements. The planets have a period of 663 ± 8 and 1818 ± 25 days, orbital eccentricities of 0.14 ± 0.08 and 0.20 ± 0.04, and minimum masses of 0.36 ± 0.04 and 0.93 ± 0.06 M_Jup. Finally, we report the discovery of a new hot-Jupiter planet around an active star, HD 103720; the planet has a period of 4.5557 ± 0.0001 days and a minimum mass of 0.62 ± 0.025 M_Jup. We discuss the fundamental parameters of these systems and limitations due to stellar activity in quiet stars with typical 2 m s^-1 radial velocity precision.