HD 20329b: An ultra-short-period planet around a solar-type star found by TESS
Journal article, 2022
Context. Ultra-short-period (USP) planets are defined as planets with orbital periods shorter than one day. This type of planets is rare, highly irradiated, and interesting because their formation history is unknown. Aims. We aim to obtain precise mass and radius measurements to confirm the planetary nature of a USP candidate found by the Transiting Exoplanet Survey Satellite (TESS). These parameters can provide insights into the bulk composition of the planet candidate and help to place constraints on its formation history. Methods. We used TESS light curves and HARPS-N spectrograph radial velocity measurements to establish the physical properties of the transiting exoplanet candidate found around the star HD 20329 (TOI-4524). We performed 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 HD 20329b, a USP planet transiting a solar-type star. The host star (HD 20329, V = 8.74 mag, J = 7.5 mag) is characterized by its G5 spectral type with M∗ = 0.90 ± 0.05 M⊙, R∗ = 1.13 ± 0.02 R⊙, and Teff = 5596 ± 50 K; it is located at a distance d = 63.68 ± 0.29 pc. By jointly fitting the available TESS transit light curves and follow-up radial velocity measurements, we find an orbital period of 0.9261 ± (0.5 ×10-4) days, a planetary radius of 1.72 ± 0.07 R∗, and a mass of 7.42 ± 1.09 M∗, implying a mean density of ρp = 8.06 ± 1.53 g cm-3. HD 20329b joins the ~30 currently known USP planets with radius and Doppler mass measurements.
Techniques: photometric
Techniques: radial velocities
Planets and satellites: detection
Author
F. Murgas
Instituto de Astrofísica de Canarias
University of La Laguna
G. Nowak
Instituto de Astrofísica de Canarias
University of La Laguna
T. Masseron
University of La Laguna
Instituto de Astrofísica de Canarias
H. Parviainen
Instituto de Astrofísica de Canarias
University of La Laguna
R. Luque
University of Chicago
Spanish National Research Council (CSIC)
Enric Palle
University of La Laguna
Instituto de Astrofísica de Canarias
Judith Korth
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Ilaria Carleo
Instituto de Astrofísica de Canarias
University of La Laguna
Szilard Csizmadia
German Aerospace Center (DLR)
E. Esparza-Borges
Instituto de Astrofísica de Canarias
University of La Laguna
A. Alqasim
University College London (UCL)
William D. Cochran
The University of Texas at Austin
Fei Dai
California Institute of Technology (Caltech)
H. Deeg
Instituto de Astrofísica de Canarias
University of La Laguna
D. Gandolfi
University of Turin
E. Goffo
University of Turin
Thüringer Landessternwarte Tautenburg
Petr Kabath
Czech Academy of Sciences
K. W.F. Lam
German Aerospace Center (DLR)
J.H. Livingston
National Institutes of Natural Sciences
National Astronomical Observatory of Japan
The Graduate University for Advanced Studies (SOKENDAI)
Alexandra Muresan
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
H. L.M. Osborne
University College London (UCL)
Carina Persson
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
L. M. Serrano
University of Turin
Alexis M. S. Smith
German Aerospace Center (DLR)
Vincent Van Eylen
University College London (UCL)
J. Orell-Miquel
University of La Laguna
Instituto de Astrofísica de Canarias
N. R. Hinkel
Southwest Research Institute
D. Galán
University of La Laguna
M. Puig-Subirà
Instituto de Astrofísica de Canarias
University of La Laguna
M. Stangret
University of La Laguna
Istituto nazionale di astrofisica (INAF)
Instituto de Astrofísica de Canarias
A. Fukui
Instituto de Astrofísica de Canarias
University of Tokyo
T. Kagetani
University of Tokyo
Norio Narita
University of Tokyo
National Institutes of Natural Sciences
Instituto de Astrofísica de Canarias
D. R. Ciardi
National Aeronautics and Space Administration (NASA)
A. W. Boyle
National Aeronautics and Space Administration (NASA)
C. Ziegler
Stephen F. Austin State University
C. Briceño
Cerro Tololo Inter American Observatory
N. Law
The University of North Carolina System
A. Mann
The University of North Carolina System
Jon M. Jenkins
National Aeronautics and Space Administration (NASA)
D. W. Latham
Harvard-Smithsonian Center for Astrophysics
Samuel N. Quinn
Harvard-Smithsonian Center for Astrophysics
George R. Ricker
Massachusetts Institute of Technology (MIT)
S. Seager
Massachusetts Institute of Technology (MIT)
Avi Shporer
University College London (UCL)
Eric B. Ting
National Aeronautics and Space Administration (NASA)
Roland K. Vanderspek
Massachusetts Institute of Technology (MIT)
J. N. Winn
Princeton University
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 668 A158Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
Ocean and River Engineering
Other Physics Topics
DOI
10.1051/0004-6361/202244459