TOI−757 b: an eccentric transiting mini−Neptune on a 17.5−d orbit
Artikel i vetenskaplig tidskrift, 2024
We report the spectroscopic confirmation and fundamental properties of TOI−757 b, a mini−Neptune on a 17.5−d orbit transiting a bright star (V = 9.7 mag) discovered by the TESS mission. We acquired high−precision radial velocity measurements with the HARPS, ESPRESSO, and PFS spectrographs to confirm the planet detection and determine its mass. We also acquired space−borne transit photometry with the CHEOPS space telescope to place stronger constraints on the planet radius, supported with ground−based LCOGT photometry. WASP and KELT photometry were used to help constrain the stellar rotation period. We also determined the fundamental parameters of the host star. We find that TOI−757 b has a radius of Rp = 2.5 ± 0.1R. and a mass of Mp = 10.5+−2212M, implying a bulk density of ρp = 3.6 ± 0.8 g cm−3. Our internal composition modelling was unable to constrain the composition of TOI−757 b, highlighting the importance of atmospheric observations for the system. We also find the planet to be highly eccentric with e = 0.39+−000708, making it one of the very few highly eccentric planets among precisely characterized mini−Neptunes. Based on comparisons to other similar eccentric systems, we find a likely scenario for TOI−757 b’s formation to be high eccentricity migration due to a distant outer companion. We additionally propose the possibility of a more intrinsic explanation for the high eccentricity due to star−star interactions during the earlier epoch of the Galactic disc formation, given the low metallicity and older age of TOI−757.
planets and satellites: interiors
planets and satellites: composition
techniques: radial velocities
techniques: photometric
stars: individual: TOI-757 (TIC 130924120)
Författare
A. Alqasim
University College London (UCL)
N. Grieves
Université de Genève
N. M. Rosário
Universidade do Porto
D. Gandolfi
Universita degli Studi di Torino
J.H. Livingston
University of Tokyo
S.G. Sousa
Universidade do Porto
Karen A. Collins
Harvard-Smithsonian Center for Astrophysics
J. K. Teske
Carnegie Institution of Washington
Malcolm Fridlund
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
J. A. Egger
Universität Bern
J. Cabrera
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Coel Hellier
Keele University
A. F. Lanza
Istituto nazionale di astrofisica (INAF)
Vincent Van Eylen
University College London (UCL)
F. Bouchy
Université de Genève
R.J. Oelkers
Texas A&M University
G. Srdoc
Kotizarovci Observatory
T.G. Wilson
Europeiska rymdorganisationen (ESA)
E. Goffo
Universita degli Studi di Torino
L. Delrez
Technische Universität Graz
Ramotholo Sefako
Universita degli Studi di Torino
S.C.C. Barros
The University of Warwick
Kevin I. Collins
Stockholms universitet
A. Heitzmann
Tsinghua University
A. Bonfanti
Université de Genève
T. Bárczy
Universität Bern
D. Barrado Navascues
Universität Bern
N. Billot
South African Astronomical Observatory
L. Borsato
Universidade do Porto
C. Broeg
George Mason University
R. Alonso
Aarhus Universitet
J. Asquier
Europeiska rymdorganisationen (ESA)
W. Baumjohann
Université de Genève
W. Benz
Universität Bern
E. Bryant
University College London (UCL)
R.P. Butler
Carnegie Institution of Washington
A. Collier Cameron
University of Texas
A. Correia
University of St Andrews
J.D. Crane
Carnegie Observatories
P. E. Cubillos
Université de Genève
M. B. Davies
Istituto nazionale di astrofisica (INAF)
A. Deline
Université de Genève
B.O. Demory
Universität Bern
M. Deleuil
Europeiska rymdorganisationen (ESA)
William D. Cochran
Istituto nazionale di astrofisica (INAF)
Szilard Csizmadia
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
A. Derekas
Laboratoire d'Astrophysique de Marseille
Billy Edwards
Eötvös Loránd University (ELTE)
Tansu Daylan
Lunds universitet
Anders Erikson
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
K. Gazeas
University of New Mexico
M. Gudel
University of Athens
J. Hasiba
Université de Genève
A. Hatzes
Thüringer Landessternwarte Tautenburg
Ch. Helling
Thüringer Landessternwarte Tautenburg
T. Hirano
Universität Wien
Jon M. Jenkins
National Astronomical Observatory of Japan
S. Kanodia
Carnegie Institution of Washington
L. L. Kiss
National Aeronautics and Space Administration (NASA)
J. Laskar
Lunds universitet
A. L. des Etangs
Observatoire de Paris
M. Lendl
Université de Genève
M. B. Lund
Institut d 'Astrophysique de Paris
R. Luque
California Institute of Technology (Caltech)
A. Mann
University of Chicago
D. Magrin
Europeiska rymdorganisationen (ESA)
P. Maxted
Keele University
C. Mordasini
Universität Bern
A. Fortier
Universität Bern
G. Olofsson
The University of Warwick
D. Ehrenreich
Université de Genève
I. Pagano
Istituto nazionale di astrofisica (INAF)
Valerio Nascimbeni
University of Athens
H. P. Osborn
Europeiska rymdorganisationen (ESA)
N. Rando
Europeiska rymdorganisationen (ESA)
R. Ottensamer
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
K. Isaak
Europeiska rymdorganisationen (ESA)
Judith Korth
Eötvös Loránd University (ELTE)
Michaël Gillon
Universität Bern
G. Peter
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Giampaolo P. Piotto
Uniwersytet Mikolaja Kopernika
S. Hoyer
Washington University in St. Louis
S.B. Howell
National Astronomical Observatory of Japan
M. Rieder
Universität Bern
E. Palle
Aarhus Universitet
Zahra Essack
Université de Genève
K. W.F. Lam
Europeiska rymdorganisationen (ESA)
Roberto Ragazzoni
Université de Genève
H. Rauer
Universidade do Porto
S. Redfield
Istituto nazionale di astrofisica (INAF)
I. Ribas
Uniwersytet Mikolaja Kopernika
D. Segransan
Université de Genève
George R. Ricker
Uniwersytet Mikolaja Kopernika
N. C. Santos
Universität Bern
Gaetano Scandariato
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
M. Stalport
Universität Bern
Avi Shporer
Carnegie Observatories
A.E. Simon
National Astronomical Observatory of Japan
Alexis M. S. Smith
Université de Genève
G.M. Szabó
Uniwersytet Mikolaja Kopernika
J. D. Twicken
Universite de Liège
S. Udry
Université de Genève
Roland K. Vanderspek
Aarhus Universitet
V. Van Grootel
Uniwersytet Mikolaja Kopernika
J. Venturini
Europeiska rymdorganisationen (ESA)
V. Viotto
Europeiska rymdorganisationen (ESA)
N. A. Walton
SETI Institute
J. N. Winn
University of Cambridge
S.W. Yee
Harvard-Smithsonian Center for Astrophysics
Monthly Notices of the Royal Astronomical Society
00358711 (ISSN) 13652966 (eISSN)
Vol. 533 1 1-26Ämneskategorier (SSIF 2011)
Astronomi, astrofysik och kosmologi
DOI
10.1093/mnras/stae1767