TOI-674b: An oasis in the desert of exo-Neptunes transiting a nearby M dwarf
Journal article, 2021
Context. The NASA mission TESS is currently doing an all-sky survey from space to detect transiting planets around bright stars. As part of the validation process, the most promising planet candidates need to be confirmed and characterized using follow-up observations. Aims. In this article, our aim is to confirm the planetary nature of the transiting planet candidate TOI-674b using spectroscopic and photometric observations. Methods. We use TESS, Spitzer, ground-based light curves, and HARPS spectrograph radial velocity measurements to establish the physical properties of the transiting exoplanet candidate TOI-674b. We perform a joint fit of the light curves and radial velocity time series to measure the mass, radius, and orbital parameters of the candidate. Results. We confirm and characterize TOI-674b, a low-density super-Neptune transiting a nearby M dwarf. The host star (TIC 158588995, V = 14.2 mag, J = 10.3 mag) is characterized by its M2V spectral type with M = 0.420 ± 0.010 M , R = 0.420 ± 0.013 R , and Teff = 3514 ± 57 K; it is located at a distance d = 46.16 ± 0.03 pc. Combining the available transit light curves plus radial velocity measurements and jointly fitting a circular orbit model, we find an orbital period of 1.977143 ± 3 × 10-6 days, a planetary radius of 5.25 ± 0.17 R , and a mass of 23.6 ± 3.3 M implying a mean density of ρp =0.91 ± 0.15 g cm-3. A non-circular orbit model fit delivers similar planetary mass and radius values within the uncertainties. Given the measured planetary radius and mass, TOI-674b is one of the largest and most massive super-Neptune class planets discovered around an M-type star to date. It is found in the Neptunian desert, and is a promising candidate for atmospheric characterization using the James Webb Space Telescope.
Stars: individual: TOI-674
Techniques: photometric
Techniques: radial velocities
Planets and satellites: general
Planets and satellites: gaseous planets
Author
F. Murgas
Instituto de Astrofísica de Canarias
University of La Laguna
N. Astudillo-Defru
Universidad Catolica de la Santisima Concepcion
X. Bonfils
Grenoble Alpes University
I. J.M. Crossfield
University of Kansas
J. M. Almenara
Grenoble Alpes University
J.H. Livingston
University of Tokyo
Keivan G. Stassun
Vanderbilt University
Judith Korth
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
J. Orell-Miquel
Instituto de Astrofísica de Canarias
University of La Laguna
Giuseppe Morello
University of La Laguna
Instituto de Astrofísica de Canarias
J. D. Eastman
Harvard-Smithsonian Center for Astrophysics
Jack J. Lissauer
National Aeronautics and Space Administration (NASA)
S. R. Kane
University of California
F. Y. Morales
California Institute of Technology (Caltech)
M. W. Werner
Universidad Catolica de la Santisima Concepcion
V. Gorjian
Universidad Catolica de la Santisima Concepcion
B. Benneke
Université de Montréal
D. Dragomir
University of New Mexico
Elisabeth Matthews
University of Geneva
S.B. Howell
National Aeronautics and Space Administration (NASA)
D. R. Ciardi
California Institute of Technology (Caltech)
Erica J. Gonzales
University of California
Rachel A. Matson
US Naval Observatory
C. Beichman
California Institute of Technology (Caltech)
Joshua E. Schlieder
National Aeronautics and Space Administration (NASA)
Karen A. Collins
Harvard-Smithsonian Center for Astrophysics
Kevin I. Collins
George Mason University
Eric L.N. Jensen
Swarthmore College
P. Evans
El Sauce Observatory
Francisco J. Pozuelos
University of Liège
Michaël Gillon
University of Liège
Emmanuel Jehin
University of Liège
Khalid Barkaoui
University of Liège
Cadi Ayyad University
E. Artigau
Consejo Nacional de Investigaciones Cientificas y Tecnicas
F. Bouchy
University of Geneva
D. Charbonneau
Harvard-Smithsonian Center for Astrophysics
X. Delfosse
Grenoble Alpes University
R. F. Diaz
Consejo Nacional de Investigaciones Cientificas y Tecnicas
René Doyon
Université de Montréal
P. Figueira
European Southern Observatory Santiago
University of Porto
T. Forveille
Grenoble Alpes University
C. Lovis
University of Geneva
C. Melo
European Southern Observatory Santiago
G. Gaisné
Grenoble Alpes University
Francesco Pepe
University of Geneva
N. C. Santos
University of Porto
D. Segransan
University of Geneva
S. Udry
University of Geneva
Robert Goeke
Massachusetts Institute of Technology (MIT)
A. M. Levine
Massachusetts Institute of Technology (MIT)
E. V. Quintana
National Aeronautics and Space Administration (NASA)
N. Guerrero
Massachusetts Institute of Technology (MIT)
Ismael Mireles
Massachusetts Institute of Technology (MIT)
D. A. Caldwell
National Aeronautics and Space Administration (NASA)
SETI Institute
P. Tenenbaum
National Aeronautics and Space Administration (NASA)
SETI Institute
C. E. Brasseur
Space Telescope Science Institute (STScI)
George R. Ricker
Massachusetts Institute of Technology (MIT)
Roland K. Vanderspek
Massachusetts Institute of Technology (MIT)
D. W. Latham
Harvard-Smithsonian Center for Astrophysics
S. Seager
Massachusetts Institute of Technology (MIT)
J. N. Winn
Princeton University
Jon M. Jenkins
National Aeronautics and Space Administration (NASA)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 653 A60Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
Ocean and River Engineering
Other Physics Topics
DOI
10.1051/0004-6361/202140718