A warm super-Neptune around the G-dwarf star TOI-1710 revealed with TESS, SOPHIE, and HARPS-N

P. -C. König (1) , M. Damasso , G. Hébrard (1, 2) , L. Naponiello , P. Cortés-Zuleta (3) , K. Biazzo , N. C. Santos , A. S. Bonomo , A. Lecavelier Des Étangs (1) , L. Zeng , S. Hoyer (3) , A. Sozzetti , L. Affer , J. M. Almenara (4) , S. Benatti , A. Bieryla , I. Boisse (3) , X. Bonfils (4) , W. Boschin , A. Carmona (4) , R. Claudi , K. A. Collins , S. Dalal (1) , M. Deleuil (3) , X. Delfosse (4) , O. D. S. Demangeon , S. Desidera , R. F. Díaz , T. Forveille (4) , N. Heidari (3) , G. A. J. Hussain , J. Jenkins , F. Kiefer (1, 5) , G. Lacedelli , D. W. Latham , L. Malavolta , L. Mancini , E. Martioli (1) , G. Micela , P. A. Miles-Páez , C. Moutou (6) , D. Nardiello (3) , V. Nascimbeni , M. Pinamonti , G. Piotto , G. Ricker , R. P. Schwarz , S. Seager , R. G. Stognone , P. A. Strøm (1) , R. Vanderspek , J. Winn , J. Wittrock

1 IAP - Institut d'Astrophysique de Paris
2 OHP - Observatoire de Haute-Provence
3 LAM - Laboratoire d'Astrophysique de Marseille
4 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble
5 LESIA - Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics
6 IRAP - Institut de recherche en astrophysique et planétologie

We report the discovery and characterization of the transiting extrasolar planet TOI-1710 b. It was first identified as a promising candidate by the Transiting Exoplanet Survey Satellite. Its planetary nature was then established with SOPHIE and HARPS-N spectroscopic observations via the radial-velocity method. The stellar parameters for the host star are derived from the spectra and a joint Markov chain Monte-Carlo adjustment of the spectral energy distribution and evolutionary tracks of TOI-1710. A joint MCMC analysis of the TESS light curve and the radial-velocity evolution allows us to determine the planetary system properties. From our analysis, TOI-1710 b is found to be a massive warm super-Neptune (M_p = 28.3 ± 4.7 M_⊕ and R_p = 5.34 ± 0.11 R_⊕) orbiting a G5V dwarf star (T_eff = 5665 ± 55 K) on a nearly circular 24.3-day orbit (e = 0.16 ± 0.08). The orbital period of this planet is close to the estimated rotation period of its host star P_rot = 22.5 ± 2.0 days and it has a low Keplerian semi-amplitude K = 6.4 ± 1.0 m s⁻¹; we thus performed additional analyses to show the robustness of the retrieved planetary parameters. With a low bulk density of 1.03 ± 0.23 g cm⁻³ and orbiting a bright host star (J = 8.3, V = 9.6), TOI-1710 b is one of the best targets in this mass-radius range (near the Neptunian desert) for atmospheric characterization via transmission spectroscopy, a key measurement in constraining planet formation and evolutionary models of sub-Jovian planets.

Keywords: planetary systems; techniques: photometric; techniques: spectroscopic; techniques: radial velocities; star: activity; Astrophysics - Earth and Planetary Astrophysics

Domains: Sciences of the Universe [physics]; Astrophysics [astro-ph]

P. -C. König, M. Damasso, G. Hébrard, L. Naponiello, P. Cortés-Zuleta, et al.. A warm super-Neptune around the G-dwarf star TOI-1710 revealed with TESS, SOPHIE, and HARPS-N. Astronomy and Astrophysics - A&A, 2022, 666, ⟨10.1051/0004-6361/202143002⟩. ⟨insu-03839639⟩