HD219666b: A hot-Neptune from TESS Sector 1

Journal
Date Issued
2019
Author(s)
Esposito, M.
•
Armstrong, D. J.
•
Gandolfi, D.
•
Adibekyan, V.
•
Fridlund, M.
•
Santos, N. C.
•
Livingston, J. H.
•
Delgado Mena, E.
•
Fossati, L.
•
Lillo-Box, J.
•
Barragán, O.
•
Barrado, D.
•
Cubillos, P. E.
•
Cooke, B.
•
Justesen, A. B.
•
Meru, F.
•
Díaz, R. F.
•
Dai, F.
•
Nielsen, L. D.
•
Persson, C. M.
•
Wheatley, P. J.
•
Hatzes, A. P.
•
Van Eylen, V.
•
Musso, M. M.
•
Alonso, R.
•
Beck, P.
•
Barros, S. C. C.
•
Bayliss, D.
•
•
Bouchy, F.
•
Brown, D. J. A.
•
Bryant, E.
•
Cabrera, J.
•
Cochran, W. D.
•
Csizmadia, S.
•
Deeg, H.
•
Demangeon, O.
•
Deleuil, M.
•
Dumusque, X.
•
Eigmüller, P.
•
Endl, M.
•
Erikson, A.
•
Faedi, F.
•
Figueira, P.
•
Fukui, A.
•
Grziwa, S.
•
Guenther, E. W.
•
Hidalgo, D.
•
Hjorth, M.
•
Hirano, T.
•
Hojjatpanah, S.
•
Knudstrup, E.
•
Korth, J.
•
Lam, K. W. F.
•
de Leon, J.
•
Lund, M. N.
•
Luque, R.
•
Mathur, S.
•
Montañés Rodríguez, P.
•
Narita, N.
•
Nespral, D.
•
Niraula, P.
•
Nowak, G.
•
Osborn, H. P.
•
Pallé, E.
•
Pätzold, M.
•
Pollacco, D.
•
Prieto-Arranz, J.
•
Rauer, H.
•
Redfield, S.
•
Ribas, I.
•
Sousa, S. G.
•
Smith, A. M. S.
•
Tala-Pinto, M.
•
Udry, S.
•
Winn, J. N.
DOI
Abstract
We report on the confirmation and mass determination of a transiting planet orbiting the old and inactive G7 dwarf star HD219666 (Mstar = 0.92 +/- 0.03 MSun, Rstar = 1.03 +/- 0.03 RSun, tau_star = 10 +/- 2 Gyr). With a mass of Mb = 16.6 +/- 1.3 MEarth, a radius of Rb = 4.71 +/- 0.17 REarth, and an orbital period of P ~ 6 days, HD219666b is a new member of a rare class of exoplanets: the hot-Neptunes. The Transiting Exoplanet Survey Satellite (TESS) observed HD219666 (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 HARPS@ESO3.6m. 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 atmospheric metal-to-hydrogen content and thermal structure could provide us with important clues on the formation mechanisms of this class of objects.
Volume
623
Start page
A165
Uri
Url
Issn Identifier
0004-6361
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Espositoetal_2019.pdf

Description
PDF editoriale
Size

1.68 MB

Format

Adobe PDF

Checksum (MD5)

71db4f62f403198a93b4646fe6cc4812