A Radial Velocity Study of the Planetary System of π Mensae: Improved Planet Parameters for pi Mensae c and a Third Planet on a 125 Day Orbit
Journal article, 2022
π Men hosts a transiting planet detected by the Transiting Exoplanet Survey Satellite space mission and an outer planet in a 5.7 yr orbit discovered by radial velocity (RV) surveys. We studied this system using new RV measurements taken with the HARPS spectrograph on ESO's 3.6 m telescope, as well as archival data. We constrain the stellar RV semiamplitude due to the transiting planet, π Men c, as K c = 1.21 ± 0.12 m s-1, resulting in a planet mass of M c = 3.63 ± 0.38 M. A planet radius of R c = 2.145 ± 0.015 R yields a bulk density of ρ c = 2.03 ± 0.22 g cm-3. The precisely determined density of this planet and the brightness of the host star make π Men c an excellent laboratory for internal structure and atmospheric characterization studies. Our HARPS RV measurements also reveal compelling evidence for a third body, π Men d, with a minimum mass M d sin i d = 13.38 ± 1.35 M orbiting with a period of P orb,d = 125 days on an eccentric orbit (e d = 0.22). A simple dynamical analysis indicates that the orbit of π Men d is stable on timescales of at least 20 Myr. Given the mutual inclination between the outer gaseous giant and the inner rocky planet and the presence of a third body at 125 days, π Men is an important planetary system for dynamical and formation studies.
Author
A. Hatzes
University of Turin
D. Gandolfi
University of Turin
Judith Korth
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
F. Rodler
European Southern Observatory Santiago
S. Sabotta
Heidelberg-Königstuhl State Observatory
M. Esposito
Thüringer Landessternwarte Tautenburg
O. Barragán
University of Oxford
Vincent Van Eylen
University College London (UCL)
J.H. Livingston
University of Tokyo
L. M. Serrano
University of Turin
R. Luque
Institute of Astrophysics of Andalusia (IAA)
Alexis M. S. Smith
German Aerospace Center (DLR)
S. Redfield
Wesleyan University
Carina Persson
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Martin Pätzold
University of Cologne
Enric Palle
University of La Laguna
Instituto de Astrofísica de Canarias
G. Nowak
University of La Laguna
Instituto de Astrofísica de Canarias
H. L.M. Osborne
University College London (UCL)
Norio Narita
National Astronomical Observatory of Japan
Japan Science and Technology Agency
Instituto de Astrofísica de Canarias
University of Tokyo
National Institutes of Natural Sciences
S. Mathur
University of La Laguna
Instituto de Astrofísica de Canarias
K. W.F. Lam
Technische Universität Berlin
Petr Kabath
Czech Academy of Sciences
M.C. Johnson
Las Cumbres Observatory Global Telescope Network
E. W. Guenther
Thüringer Landessternwarte Tautenburg
S. Grziwa
University of Cologne
E. Goffo
University of Turin
Malcolm Fridlund
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Leiden University
M. Endl
The University of Texas at Austin
H. Deeg
Instituto de Astrofísica de Canarias
University of La Laguna
Szilárd Csizmadia
German Aerospace Center (DLR)
William D. Cochran
The University of Texas at Austin
Lucá Gonzalez Cuesta
University of La Laguna
Instituto de Astrofísica de Canarias
Priyanka Chaturvedi
Thüringer Landessternwarte Tautenburg
Ilaria Carleo
Wesleyan University
J. Cabrera
German Aerospace Center (DLR)
P. G. Beck
University of Graz
Simon Albrecht
Aarhus University
Astronomical Journal
0004-6256 (ISSN) 1538-3881 (eISSN)
Vol. 163 5 223Exoplanets from space -CHEOPS and PLATO ESA's next two projects (Phase 2)
Swedish National Space Board (177/19), 2020-01-01 -- 2022-12-31.
Swedish National Space Board (65/19), 2020-01-01 -- 2022-12-31.
Subject Categories
Astronomy, Astrophysics and Cosmology
Other Physics Topics
Condensed Matter Physics
DOI
10.3847/1538-3881/ac5dcb