Characterization of the HD 108236 system with CHEOPS and TESS Confirmation of a fifth transiting planet
Artikel i vetenskaplig tidskrift, 2022
Context. The HD 108236 system was first announced with the detection of four small planets based on TESS data. Shortly after, the transit of an additional planet with a period of 29.54 d was serendipitously detected by CHEOPS. In this way, HD 108236 (V = 9.2) became one of the brightest stars known to host five small transiting planets (Rp < 3 Ro˙). Aims. We characterize the planetary system by using all the data available from CHEOPS and TESS space missions. We use the flexible pointing capabilities of CHEOPS to follow up the transits of all the planets in the system, including the fifth transiting body. Methods. After updating the host star parameters by using the results from Gaia eDR3, we analyzed 16 and 43 transits observed by CHEOPS and TESS, respectively, to derive the planets' physical and orbital parameters. We carried out a timing analysis of the transits of each of the planets of HD 108236 to search for the presence of transit timing variations. Results. We derived improved values for the radius and mass of the host star (R∗ = 0.876 ± 0.007 R0 and M∗ = 0.867-0.046+0.047M). We confirm the presence of the fifth transiting planet f in a 29.54 d orbit. Thus, the HD 108236 system consists of five planets of Rb = 1.587±0.028, Rc = 2.122±0.025, Rd = 2.629 ± 0.031, Re = 3.008 ± 0.032, and Rf = 1.89 ± 0.04 [Ro˙]. We refine the transit ephemeris for each planet and find no significant transit timing variations for planets c, d, and e. For planets b and f, instead, we measure significant deviations on their transit times (up to 22 and 28 min, respectively) with a non-negligible dispersion of 9.6 and 12.6 min in their time residuals. Conclusions. We confirm the presence of planet f and find no significant evidence for a potential transiting planet in a 10.9 d orbital period, as previously suggested. Further monitoring of the transits, particularly for planets b and f, would confirm the presence of the observed transit time variations. HD 108236 thus becomes a key multi-planetary system for the study of formation and evolution processes. The reported precise results on the planetary radii - together with a profuse RV monitoring - will allow for an accurate characterization of the internal structure of these planets.
Planets and satellites: detection
Planets and satellites: individual: HD 108236
Planets and satellites: individual: TOI 1233
Planetary systems
Planets and satellites: fundamental parameters
Författare
S. Hoyer
Laboratoire d'Astrophysique de Marseille
A. Bonfanti
Institut fur Weltraumforschung
A. Leleu
Université de Genève
Universität Bern
L. Acuña
Laboratoire d'Astrophysique de Marseille
L. M. Serrano
Universita degli Studi di Torino
M. Deleuil
Laboratoire d'Astrophysique de Marseille
A. Bekkelien
Université de Genève
C. Broeg
Universität Bern
H.-G. Florén
Stockholms universitet
D. Queloz
University of Cambridge
Eidgenössische Technische Hochschule Zürich (ETH)
T.G. Wilson
University of St Andrews
S.G. Sousa
Universidade do Porto
M.J. Hooton
University of Cambridge
Universität Bern
V. Adibekyan
Universidade do Porto
Y. Alibert
Universität Bern
R. Alonso
Universidad de la Laguna
Instituto de Astrofísica de Canarias
G. Anglada
Institut d'Estudis Espacials de Catalunya (IEEC)
Institut de Ciències de l'Espai (ICE) - CSIC
J. Asquier
European Space Research and Technology Centre (ESA ESTEC)
T. Bárczy
Admatis
D. Barrado
European Space Astronomy Centre (ESAC)
S.C.C. Barros
Universidade do Porto
W. Baumjohann
Institut fur Weltraumforschung
M. Beck
Université de Genève
T. Beck
Universität Bern
W. Benz
Universität Bern
N. Billot
Université de Genève
F. Biondi
Istituto nazionale di astrofisica (INAF)
Max-Planck-Gesellschaft
X. Bonfils
Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)
A. Brandeker
Stockholms universitet
J. Cabrera
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
S. Charnoz
Institut de Physique du Globe de Paris
A. Collier Cameron
University of St Andrews
Szilard Csizmadia
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
M. B. Davies
Lunds universitet
L. Delrez
Universite de Liège
O. Demangeon
Universidade do Porto
B.O. Demory
Universität Bern
D. Ehrenreich
Université de Genève
Anders Erikson
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
A. Fortier
Universität Bern
L. Fossati
Institut fur Weltraumforschung
Malcolm Fridlund
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
Universiteit Leiden
D. Gandolfi
Universita degli Studi di Torino
Michaël Gillon
Universite de Liège
M. Gudel
Universität Wien
N.C. Hara
Université de Genève
Kevin Heng
The University of Warwick
Universität Bern
K. Isaak
European Space Research and Technology Centre (ESA ESTEC)
Jon M. Jenkins
NASA Ames Research Center
L. Kiss
Magyar Tudomanyos Akademia
Eötvös Loránd University (ELTE)
J. Laskar
Observatoire de Paris
D. W. Latham
Harvard-Smithsonian Center for Astrophysics
A. L. des Etangs
Institut d 'Astrophysique de Paris
M. Lendl
Université de Genève
C. Lovis
Université de Genève
A. Luntzer
Universität Wien
D. Magrin
Istituto nazionale di astrofisica (INAF)
P. Maxted
Keele University
Valerio Nascimbeni
Istituto nazionale di astrofisica (INAF)
G. Olofsson
Stockholms universitet
R. Ottensamer
Universität Wien
I. Pagano
Istituto nazionale di astrofisica (INAF)
Enric Palle
Instituto de Astrofísica de Canarias
Carina Persson
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
G. Peter
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
D. Piazza
Universität Bern
Giampaolo P. Piotto
Università di Padova
Istituto nazionale di astrofisica (INAF)
Don L. Pollacco
The University of Warwick
Roberto Ragazzoni
Istituto nazionale di astrofisica (INAF)
Università di Padova
N. Rando
European Space Research and Technology Centre (ESA ESTEC)
H. Rauer
Freie Universität Berlin
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Technische Universität Berlin
I. Ribas
Institut d'Estudis Espacials de Catalunya (IEEC)
Institut de Ciències de l'Espai (ICE) - CSIC
George R. Ricker
Massachusetts Institute of Technology (MIT)
S. Salmon
Université de Genève
N. C. Santos
Universidade do Porto
Gaetano Scandariato
Istituto nazionale di astrofisica (INAF)
S. Seager
Massachusetts Institute of Technology (MIT)
D. Segransan
Université de Genève
A.E. Simon
Universität Bern
Alexis M. S. Smith
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
Manfred B. Steller
Institut fur Weltraumforschung
G.M. Szabó
Eötvös Loránd University (ELTE)
Nicolas Thomas
Universität Bern
J. D. Twicken
NASA Ames Research Center
SETI Institute
S. Udry
Université de Genève
V. Van Grootel
Universite de Liège
Roland K. Vanderspek
Massachusetts Institute of Technology (MIT)
N. A. Walton
University of Cambridge
K. Westerdorff
Deutsches Zentrums für Luft- und Raumfahrt (DLR)
J. N. Winn
Princeton University
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 668 A117Exoplaneter från rymden - CHEOPS och PLATO, ESA's nästa två rymdteleskop (fas 2)
Rymdstyrelsen (177/19), 2020-01-01 -- 2022-12-31.
Rymdstyrelsen (65/19), 2020-01-01 -- 2022-12-31.
Ämneskategorier
Astronomi, astrofysik och kosmologi
Annan fysik
Teoretisk kemi
DOI
10.1051/0004-6361/202243720