Abstract

Aims: We aim to detect planetary companions to young stars with debris disks via the radial velocity method.
Methods: We observed HD 114082 during April 2018-August 2022 as one of the targets of our RVSPY program (Radial Velocity Survey for Planets around Young stars). We use the FEROS spectrograph, mounted to the MPG/ESO 2.2 m telescope in Chile, to obtain high signal-to-noise spectra and time series of precise radial velocities (RVs). Additionally, we analyze archival HARPS spectra and TESS photometric data. We use the CERES, CERES++ and SERVAL pipelines to derive RVs and activity indicators and ExoStriker for the independent and combined analysis of the RVs and TESS photometry.
Results: We report the discovery of a warm super-Jovian companion around HD 114082 based on a 109.8±0.4 day signal in the combined RV data from FEROS and HARPS, and on one transit event in the TESS photometry. The best-fit model indicates a 8.0±1.0 M_Jup companion with a radius of 1.00±0.03 R_Jup in an orbit with a semi-major axis of 0.51±0.01 au and an eccentricity of 0.4±0.04. The companions orbit is in agreement with the known near edge-on debris disk located at ∼28 au. HD 114082 b is possibly the youngest (15±6 Myr), and one of only three young (< 100 Myr) giant planetary companions for which both their mass and radius have been determined observationally. It is probably the first properly model-constraining giant planet that allows distinguishing between hot and cold-start models. It is significantly more compatible with the cold-start model.

Based on observations collected at the European Organization for Astronomical Research in the Southern Hemisphere under MPG programs 0101.A-9012, 0103.A-9010, 0104.A-9003, 0107.A-9004, 0108.A-9014, 0109.A-9014 and ESO programs 098.C-0739, 1101.C-0557.