Improved characterization of the TOI-2141 system: A dense sub-Neptune with non-transiting inner and outer companions
Journal article, 2025
Aims. We aim to refine the fundamental parameters of the TOI-2141 planetary system, which includes a transiting sub-Neptune orbiting a Sun-like star on a relatively long orbit of 18.26 days, by combining new photometric and spectroscopic observations.
Methods. We analyzed new space-based photometry from TESS and CHEOPS, as well as 61 radial velocity measurements from HARPS-N. We performed individual and joint photometric and RV analyses using several modeling tools within a Bayesian model comparison framework.
Results. We refined the radius and mass of the transiting planet TOI-2141 b to 3.15 ± 0.04 R ⊕ and 20.1 ± 1.6 M ⊕ to levels that are five and two times more precise, respectively, than the previously reported values. Our radial velocity analysis reveals two additional non-transiting companions with orbital periods of 5.46 and 60.45 days. Despite the innermost planet’s high geometric transit probability, we found no evidence of transits in the photometric data.
Conclusions. The bulk properties of TOI-2141 b suggest a significant volatile envelope atop an Earth-like core. The modeling indicates a hydrogen-rich atmosphere that could have experienced mild photoevaporation over the system’s history. Planets b and c are believed to exhibit a modest mutual inclination of at least ~2.4°.
Methods. We analyzed new space-based photometry from TESS and CHEOPS, as well as 61 radial velocity measurements from HARPS-N. We performed individual and joint photometric and RV analyses using several modeling tools within a Bayesian model comparison framework.
Results. We refined the radius and mass of the transiting planet TOI-2141 b to 3.15 ± 0.04 R ⊕ and 20.1 ± 1.6 M ⊕ to levels that are five and two times more precise, respectively, than the previously reported values. Our radial velocity analysis reveals two additional non-transiting companions with orbital periods of 5.46 and 60.45 days. Despite the innermost planet’s high geometric transit probability, we found no evidence of transits in the photometric data.
Conclusions. The bulk properties of TOI-2141 b suggest a significant volatile envelope atop an Earth-like core. The modeling indicates a hydrogen-rich atmosphere that could have experienced mild photoevaporation over the system’s history. Planets b and c are believed to exhibit a modest mutual inclination of at least ~2.4°.
techniques: radial velocities
planets and satellites: individual: TOI-2141b
stars: solar-type
planets and satellites: detection
techniques: photometric
Author
R. Luque
Spanish National Research Council (CSIC)
K. W.F. Lam
German Aerospace Center (DLR)
J. Cabrera
German Aerospace Center (DLR)
A. Bonfanti
Institut fur Weltraumforschung
Yoshi Eschen
The University of Warwick
G. Olofsson
Stockholm University
W. Benz
Physics Institute
University of Bern
N. Billot
University of Geneva
A. Brandeker
Stockholm University
A. Correia
University of Coimbra
L. Fossati
Institut fur Weltraumforschung
D. Gandolfi
University of Turin
H. P. Osborn
Swiss Federal Institute of Technology in Zürich (ETH)
University of Bern
C. Pezzotti
University of Liège
S.G. Sousa
University of Porto
T.G. Wilson
The University of Warwick
S. Wolf
Physics Institute
Y. Alibert
University of Bern
Physics Institute
R. Alonso
University of La Laguna
Instituto de Astrofísica de Canarias
J. Asquier
European Space Agency (ESA)
T. Bárczy
Admatis
D. Barrado
Centro de Astrobiologia (CAB)
S.C.C. Barros
University of Porto
W. Baumjohann
Institut fur Weltraumforschung
F. Biondi
Istituto nazionale di astrofisica (INAF)
Max Planck Society
L. Borsato
Istituto nazionale di astrofisica (INAF)
C. Broeg
University of Bern
Physics Institute
A. Collier Cameron
University of St Andrews
Szilard Csizmadia
German Aerospace Center (DLR)
P. E. Cubillos
Institut fur Weltraumforschung
Istituto nazionale di astrofisica (INAF)
Melvyn B. Davies
Lund University
M. Deleuil
Laboratoire d'Astrophysique de Marseille
A. Deline
University of Geneva
O. Demangeon
University of Porto
B.O. Demory
University of Bern
Physics Institute
A. Derekas
Eötvös Loránd University (ELTE)
Billy Edwards
Netherlands Institute for Space Research (SRON)
J. A. Egger
Physics Institute
D. Ehrenreich
University of Geneva
Anders Erikson
German Aerospace Center (DLR)
A. Fortier
University of Bern
Physics Institute
Malcolm Fridlund
Leiden University
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
K. Gazeas
University of Athens
Michaël Gillon
University of Liège
M. Gudel
University of Vienna
Maximilian N. Günther
European Space Agency (ESA)
A. Heitzmann
University of Geneva
Ch. Helling
Technische Universität Graz
Institut fur Weltraumforschung
K. Isaak
European Space Agency (ESA)
Tatiana Keller
University of Bern
Physics Institute
L. L. Kiss
Hungarian Academy of Sciences
Eötvös Loránd University (ELTE)
Judith Korth
University of Geneva
J. Laskar
Paris Observatory
A. L. des Etangs
Institut d 'Astrophysique de Paris
A. Leleu
Physics Institute
University of Geneva
M. Lendl
University of Geneva
D. Magrin
Istituto nazionale di astrofisica (INAF)
G. Mantovan
Istituto nazionale di astrofisica (INAF)
University of Padua
P. Maxted
Keele University
Bruno Merín
European Space Agency (ESA)
C. Mordasini
Physics Institute
University of Bern
Valerio Nascimbeni
Istituto nazionale di astrofisica (INAF)
R. Ottensamer
University of Vienna
I. Pagano
Istituto nazionale di astrofisica (INAF)
Enric Palle
Instituto de Astrofísica de Canarias
University of La Laguna
G. Peter
German Aerospace Center (DLR)
D. Piazza
University of Bern
Giampaolo P. Piotto
University of Padua
Istituto nazionale di astrofisica (INAF)
Don L. Pollacco
The University of Warwick
D. Queloz
University of Cambridge
Swiss Federal Institute of Technology in Zürich (ETH)
Roberto Ragazzoni
University of Padua
Istituto nazionale di astrofisica (INAF)
N. Rando
European Space Agency (ESA)
H. Rauer
Freie Universität Berlin
German Aerospace Center (DLR)
I. Ribas
Spanish National Research Council (CSIC)
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
N. C. Santos
University of Porto
Gaetano Scandariato
Istituto nazionale di astrofisica (INAF)
D. Segransan
University of Geneva
A.E. Simon
Physics Institute
University of Bern
A. M.S. Smith
German Aerospace Center (DLR)
M. Stalport
University of Liège
S. Sulis
Laboratoire d'Astrophysique de Marseille
G.M. Szabó
Eötvös Loránd University (ELTE)
S. Udry
University of Geneva
B. Ulmer
German Aerospace Center (DLR)
S. Ulmer-Moll
University of Cambridge
University of Liège
V. Van Grootel
University of Liège
J. Venturini
University of Geneva
E. Villaver
University of La Laguna
Instituto de Astrofísica de Canarias
N. A. Walton
University of Cambridge
D. Wolter
German Aerospace Center (DLR)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 704 A174Subject Categories (SSIF 2025)
Astronomy, Astrophysics, and Cosmology
DOI
10.1051/0004-6361/202556515