HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

HD 219666 b: a hot-Neptune from TESS Sector 1

Abstract : We report on the confirmation and mass determination of a transiting planet orbiting the old and inactive G7 dwarf star HD 219666 (M = 0.92 ± 0.03 M, R = 1.03 ± 0.03 R, τ = 10 ± 2 Gyr). With a mass of Mb = 16.6 ± 1.3 M, a radius of Rb = 4.71 ± 0.17 R, and an orbital period of Porb ≃ 6 days, HD 219666 b is a new member of a rare class of exoplanets: the hot-Neptunes. The Transiting Exoplanet Survey Satellite (TESS) observed HD 219666 (also known as TOI-118) in its Sector 1 and the light curve shows four transit-like events, equally spaced in time. We confirmed the planetary nature of the candidate by gathering precise radial-velocity measurements with the High Accuracy Radial velocity Planet Searcher (HARPS) at ESO 3.6 m. We used the co-added HARPS spectrum to derive the host star fundamental parameters (Teff = 5527 ± 65 K, log g = 4.40 ± 0.11 (cgs), [Fe/H]= 0.04 ± 0.04 dex, log R'HK = -5.07 ± 0.03), as well as the abundances of many volatile and refractory elements. The host star brightness (V = 9.9) makes it suitable for further characterisation by means of in-transit spectroscopy. The determination of the planet orbital obliquity, along with the atmosphericmetal-to-hydrogen content and thermal structure could provide us with important clues on the formation mechanisms of this class of objects.

Based on observations made with the 3.6 m-ESO telescope at La Silla observatory under ESO programmes IDs 1102.C-0923 (PI: Gandolfi) and 1102.C-0249 (PI: Armstrong).

Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03666765
Contributor : Nathalie Pothier Connect in order to contact the contributor
Submitted on : Friday, May 13, 2022 - 7:37:52 AM
Last modification on : Saturday, May 14, 2022 - 3:03:55 AM

File

aa34853-18.pdf
Publisher files allowed on an open archive

Identifiers

Collections

Citation

M. Esposito, D. J. Armstrong, D. Gandolfi, V. Adibekyan, M. Fridlund, et al.. HD 219666 b: a hot-Neptune from TESS Sector 1. Astronomy & Astrophysics, 2019, 623, ⟨10.1051/0004-6361/201834853⟩. ⟨insu-03666765⟩

Share

Metrics

Record views

0

Files downloads

0