Giant Outer Transiting Exoplanet Mass (GOT'EM) survey VII. TOI-6041: A multi-planet system including a warm Neptune exhibiting strong transit-timing variations
Journal article, 2026
We present the characterisation of the TOI-6041 system, a bright (V = 9.84 +/- 0.03) G7-type star hosting at least two planets. The inner planet, TOI-6041 b, is a warm Neptune with a radius of 4.55(-0.17)(+0.18)R(circle plus), initially identified as a single-transit event in TESS photometry. Subsequent observations with TESS and CHEOPS revealed additional transits, enabling the determination of its 26.04945(-0.00034)(+0.00033) orbital period and the detection of significant transit-timing variations (TTVs), exhibiting a peak-to-peak amplitude of about 1 hour. Radial-velocity (RV) measurements obtained with the APF spectrographs allowed us to place a 3 sigma upper mass limit of 28.9 M-circle plus on TOI-6041 b. In addition, the RV data reveal a second companion, TOI-6041 c, on an 88 d orbit, with a minimum mass of 0.25 M-Jup. A preliminary TTV analysis suggested that the observed variations could be caused by gravitational perturbations from planet c; however, reproducing the observed amplitudes requires a relatively high eccentricity of about 0.3 for that planet. Our dynamical stability analysis indicates that such a configuration is dynamically viable and places a 1 sigma upper limit on the mass of TOI-6041 c at 0.8 M-Jup. An alternative is the presence of a third, low-mass planet located between planets b and c, or on an inner orbit relative to planet b - particularly near a mean-motion resonance with planet b - which could account for the observed variations. These findings remain tentative, and further RV and photometric observations are essential in to better constrain the mass of planet b and to refine the TTV modeling, thereby improving our understanding of the system's dynamical architecture.
planets and satellites: detection
planets and satellites: dynamical evolution and stability
Author
N. Heidari
Institut d 'Astrophysique de Paris
Sorbonne University
A. Alnajjarine
Sorbonne University
H. P. Osborn
Swiss Federal Institute of Technology in Zürich (ETH)
University of Bern
D. Dragomir
University of New Mexico
P. Dalba
University of California
W. Benz
University of Bern
G. Hebrard
Aix Marseille University
Sorbonne University
Institut d 'Astrophysique de Paris
J. Laskar
Sorbonne University
N. Billot
University of Geneva
M. N. Gunther
European Space Agency (ESA)
T. G. Wilson
The University of Warwick
Y. Alibert
University of Bern
A. Bonfanti
Austrian Academy of Sciences
A. Bieryla
Harvard-Smithsonian Center for Astrophysics
C. Broeg
University of Bern
A. C. M. Correia
University of Coimbra
J. A. Egger
University of Bern
Z. Essack
University of New Mexico
E. Furlan
California Institute of Technology (Caltech)
D. Gandolfi
University of Turin
N. Grieves
University of Geneva
S. Howell
National Aeronautics and Space Administration (NASA)
D. LaCourse
Amateur Astronomer
C. Pezzotti
University of Liège
T. Pritchard
National Aeronautics and Space Administration (NASA)
S. G. Sousa
University of Porto
S. Ulmer-Moll
University of Liège
Leiden University
S. Villanueva
National Aeronautics and Space Administration (NASA)
R. Alonso
University of La Laguna
Instituto de Astrofísica de Canarias
J. Asquier
European Space Agency (ESA)
T. Barczy
Admatis
D. Barrado
Spanish National Research Council (CSIC)
S. C. C. Barros
University of Porto
W. Baumjohann
Austrian Academy of Sciences
L. Borsato
Istituto nazionale di astrofisica (INAF)
A. Brandeker
Stockholm University
M. Buder
German Aerospace Center (DLR)
A. Collier Cameron
University of St Andrews
S. Csizmadia
German Aerospace Center (DLR)
P. E. Cubillos
Austrian Academy of Sciences
Istituto nazionale di astrofisica (INAF)
M. B. Davies
Lund University
M. Deleuil
Aix Marseille University
X. Delfosse
Grenoble Alpes University
A. Deline
University of Geneva
O. D. S. Demangeon
University of Porto
B. Demory
University of Bern
A. Derekas
Eötvös Loránd University (ELTE)
B. Edwards
Netherlands Institute for Space Research (SRON)
D. Ehrenreich
University of Geneva
A. Erikson
German Aerospace Center (DLR)
A. Fortier
University of Bern
L. Fossati
Austrian Academy of Sciences
Malcolm Fridlund
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
K. Gazeas
National and Kapodistrian University of Athens
M. Gillon
University of Liège
M. Gudel
University of Vienna
J. Hasiba
Austrian Academy of Sciences
A. Heitzmann
University of Geneva
C. Helling
Austrian Academy of Sciences
Technische Universität Graz
J. M. Jenkins
National Aeronautics and Space Administration (NASA)
T. Keller
University of Bern
S. R. Kane
University of California
K. G. Stassun
Vanderbilt University
L. L. Kiss
Hungarian Academy of Sciences
Eötvös Loránd University (ELTE)
J. Korth
University of Geneva
K. W. F. Lam
German Aerospace Center (DLR)
D. W. Latham
Harvard-Smithsonian Center for Astrophysics
A. Lecavelier des Etangs
Pierre and Marie Curie University (UPMC)
A. Leleu
University of Bern
University of Geneva
M. Lendl
University of Geneva
P. F. L. Maxted
Keele University
S. McDermott
Protologic LLC
B. Merin
European Space Agency (ESA)
C. Mordasini
University of Bern
V. Nascimbeni
Istituto nazionale di astrofisica (INAF)
G. Nowak
Nicolaus Copernicus University (SGMK)
G. Olofsson
Stockholm University
I. Pagano
Istituto nazionale di astrofisica (INAF)
E. Palle
Instituto de Astrofísica de Canarias
University of La Laguna
G. Piotto
University of Padua
Istituto nazionale di astrofisica (INAF)
D. Pollacco
The University of Warwick
D. Queloz
Swiss Federal Institute of Technology in Zürich (ETH)
University of Cambridge
R. Ragazzoni
Istituto nazionale di astrofisica (INAF)
University of Padua
H. Rauer
German Aerospace Center (DLR)
Freie Universität Berlin
I. Ribas
Inst Estudis Espacials Catalunya IEEC
Spanish National Research Council (CSIC)
G. Ricker
Massachusetts Institute of Technology (MIT)
N. C. Santos
University of Porto
G. Scandariato
Istituto nazionale di astrofisica (INAF)
S. Seager
Massachusetts Institute of Technology (MIT)
D. Segransan
University of Geneva
A. E. Simon
University of Bern
A. M. S. Smith
German Aerospace Center (DLR)
M. Stalport
University of Liège
S. Striegel
SETI Institute
National Aeronautics and Space Administration (NASA)
S. Sulis
Aix Marseille University
G. M. Szabo
Eötvös Loránd University (ELTE)
S. Udry
University of Geneva
V. Van Grootel
University of Liège
R. Vanderspek
Massachusetts Institute of Technology (MIT)
J. Venturini
University of Geneva
E. Villaver
University of La Laguna
Instituto de Astrofísica de Canarias
V. Viotto
Istituto nazionale di astrofisica (INAF)
N. A. Walton
University of Cambridge
J. N. Winn
Princeton University
S. Wolf
Istituto nazionale di astrofisica (INAF)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 707 A134Subject Categories (SSIF 2025)
Astronomy, Astrophysics, and Cosmology
DOI
10.1051/0004-6361/202556700