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 In this paper, we present new space- and ground-based photometric data of WASP-47b and WASP-47-d, including 11 unpublished light curves from the ESA mission CHaracterising ExOPlanet Satellite (CHEOPS).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 and satellites: detection

satellites: general

techniques: photometric

planets

Author

Valerio Nascimbeni

Istituto nazionale di astrofisica (INAF)

L. Borsato

Istituto nazionale di astrofisica (INAF)

Tiziano Zingales

Istituto nazionale di astrofisica (INAF)

University of Padua

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

Instituto de Astrofísica de Canarias

University of La Laguna

G. Anglada

Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)

Spanish National Research Council (CSIC)

T. Bárczy

Admatis

D. Barrado

European Space Astronomy Centre (ESAC)

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

Institut fur Weltraumforschung

Istituto nazionale di astrofisica (INAF)

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 Research and Technology Centre (ESA ESTEC)

L.L. Kiss

Hungarian Academy of Sciences

Eötvös Loránd University (ELTE)

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

Spanish National Research Council (CSIC)

University of Chicago

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

University of Padua

Istituto nazionale di astrofisica (INAF)

N. Rando

European Space Research and Technology Centre (ESA ESTEC)

F. Ratti

European Space Research and Technology Centre (ESA ESTEC)

H. Rauer

Freie Universität Berlin

Technische 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

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 A42

Subject Categories (SSIF 2011)

Astronomy, Astrophysics and Cosmology

DOI

10.1051/0004-6361/202245486

More information

Latest update

3/9/2025 1