A new dynamical modeling of the WASP-47 system with CHEOPS observations
Journal article, 2023
Among the hundreds of known hot Jupiters (HJs), only five have been found to have companions on short-period orbits. Within this rare class of multiple planetary systems, the architecture of WASP-47 is unique, hosting an HJ (planet-b) with both an inner and an outer sub-Neptunian mass companion (-e and -d, respectively) as well as an additional non-transiting, long-period giant (-c). The small period ratio between planets -b and -d boosts the transit time variation (TTV) signal, making it possible to reliably measure the masses of these planets in synergy with the radial velocity (RV) technique. In this paper, we present new space- and ground-based photometric data of WASP-47b and WASP-47-d, including 11 unpublished light curves from the ESA mission CHaracterising ExOPlanet Satellite (CHEOPS). We analyzed the light curves in a homogeneous way together with all the publicly available data to carry out a global N-body dynamical modeling of the TTV and RV signals. We retrieved, among other parameters, a mass and density for planet -d of Md = 15.5 ± 0.8 M⊕ and ρd = 1.69 ± 0.22 g cm−3, which is in good agreement with the literature and consistent with a Neptune-like composition. For the inner planet (-e), we found a mass and density of Me = 9.0 ± 0.5 M⊕ and ρe = 8.1 ± 0.5 g cm−3, suggesting an Earth-like composition close to other ultra-hot planets at similar irradiation levels. Though this result is in agreement with previous RV plus TTV studies, it is not in agreement with the most recent RV analysis (at 2.8σ), which yielded a lower density compatible with a pure silicate composition. This discrepancy highlights the still unresolved issue of suspected systematic offsets between RV and TTV measurements. In this paper, we also significantly improve the orbital ephemerides of all transiting planets, which will be crucial for any future follow-up.
planets
techniques: photometric
planets and satellites: detection
satellites: general
Author
Valerio Nascimbeni
Istituto nazionale di astrofisica (INAF)
L. Borsato
Istituto nazionale di astrofisica (INAF)
Tiziano Zingales
University of Padua
Istituto nazionale di astrofisica (INAF)
Giampaolo P. Piotto
University of Padua
Istituto nazionale di astrofisica (INAF)
I. Pagano
Istituto nazionale di astrofisica (INAF)
M. Beck
University of Geneva
C. Broeg
University of Bern
D. Ehrenreich
University of Geneva
S. Hoyer
Laboratoire d'Astrophysique de Marseille
F. Z. Majidi
Istituto nazionale di astrofisica (INAF)
University of Padua
V. Granata
Istituto nazionale di astrofisica (INAF)
University of Padua
S. G. Sousa
University of Porto
T.G. Wilson
University of St Andrews
V. Van Grootel
University of Liège
A. Bonfanti
Institut fur Weltraumforschung
S. Salmon
University of Geneva
A. J. Mustill
Lund University
L. Delrez
University of Liège
Y. Alibert
University of Bern
R. Alonso
University of La Laguna
Instituto de Astrofísica de Canarias
G. Anglada
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Spanish National Research Council (CSIC)
T. Bárczy
Admatis
D. Barrado
European Space Agency (ESA)
S.C.C. Barros
University of Porto
W. Baumjohann
Institut fur Weltraumforschung
T. Beck
University of Bern
W. Benz
University of Bern
M. Bergomi
Istituto nazionale di astrofisica (INAF)
N. Billot
University of Geneva
X. Bonfils
Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)
A. Brandeker
Stockholm University
J. Cabrera
German Aerospace Center (DLR)
S. Charnoz
Institut de Physique du Globe de Paris
A. Collier Cameron
University of St Andrews
Szilard Csizmadia
German Aerospace Center (DLR)
P. E. Cubillos
Istituto nazionale di astrofisica (INAF)
Institut fur Weltraumforschung
M. 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
Anders Erikson
German Aerospace Center (DLR)
A. Fortier
University of Bern
L. Fossati
Institut fur Weltraumforschung
Malcolm Fridlund
Leiden University
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
D. Gandolfi
University of Turin
Michaël Gillon
University of Liège
M. Gudel
University of Vienna
K. Isaak
European Space Agency (ESA)
L.L. Kiss
Eötvös Loránd University (ELTE)
Hungarian Academy of Sciences
J. Laskar
Paris Observatory
A. L. des Etangs
Institut d 'Astrophysique de Paris
M. Lendl
University of Geneva
C. Lovis
University of Geneva
R. Luque
University of Chicago
Spanish National Research Council (CSIC)
D. Magrin
Istituto nazionale di astrofisica (INAF)
P. Maxted
Keele University
C. Mordasini
University of Bern
G. Olofsson
Stockholm University
R. Ottensamer
University of Vienna
E. Palle
Instituto de Astrofísica de Canarias
G. Peter
German Aerospace Center (DLR)
D. Piazza
University of Bern
D. Pollacco
The University of Warwick
D. Queloz
Swiss Federal Institute of Technology in Zürich (ETH)
University of Cambridge
Roberto Ragazzoni
Istituto nazionale di astrofisica (INAF)
University of Padua
N. Rando
European Space Agency (ESA)
F. Ratti
European Space Agency (ESA)
H. Rauer
Freie Universität Berlin
Technische Universität Berlin
German Aerospace Center (DLR)
I. Ribas
Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Spanish National Research Council (CSIC)
N. C. Santos
University of Porto
Gaetano Scandariato
Istituto nazionale di astrofisica (INAF)
D. Segransan
University of Geneva
A.E. Simon
University of Bern
A. M.S. Smith
German Aerospace Center (DLR)
M. Steinberger
Institut fur Weltraumforschung
Manfred B. Steller
Institut fur Weltraumforschung
G.M. Szabó
Eötvös Loránd University (ELTE)
N. Thomas
University of Bern
S. Udry
University of Geneva
J. Venturini
University of Geneva
N. A. Walton
University of Cambridge
D. Wolter
German Aerospace Center (DLR)
Astronomy and Astrophysics
0004-6361 (ISSN) 1432-0746 (eISSN)
Vol. 673 A42Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
DOI
10.1051/0004-6361/202245486