Connecting photometric and spectroscopic granulation signals with CHEOPS and ESPRESSO
Journal article, 2023
Context. Stellar granulation generates fluctuations in photometric and spectroscopic data whose properties depend on the stellar type, composition, and evolutionary state. Characterizing granulation is key for understanding stellar atmospheres and detecting planets. Aims. We aim to detect the signatures of stellar granulation, link spectroscopic and photometric signatures of convection for main-sequence stars, and test predictions from 3D hydrodynamic models. Methods. For the first time, we observed two bright stars (Teff = 5833 and 6205 K) with high-precision observations taken simultaneously with CHEOPS and ESPRESSO. We analyzed the properties of the stellar granulation signal in each individual dataset. We compared them to Kepler observations and 3D hydrodynamic models. While isolating the granulation-induced changes by attenuating and filtering the p-mode oscillation signals, we studied the relationship between photometric and spectroscopic observables. Results. The signature of stellar granulation is detected and precisely characterized for the hotter F star in the CHEOPS and ESPRESSO observations. For the cooler G star, we obtain a clear detection in the CHEOPS dataset only. The TESS observations are blind to this stellar signal. Based on CHEOPS observations, we show that the inferred properties of stellar granulation are in agreement with both Kepler observations and hydrodynamic models. Comparing their periodograms, we observe a strong link between spectroscopic and photometric observables. Correlations of this stellar signal in the time domain (flux versus radial velocities, RV) and with specific spectroscopic observables (shape of the cross-correlation functions) are however difficult to isolate due to S/N dependent variations. Conclusions. In the context of the upcoming PLATO mission and the extreme precision RV surveys, a thorough understanding of the properties of the stellar granulation signal is needed. The CHEOPS and ESPRESSO observations pave the way for detailed analyses of this stellar process.
Sun: granulation
Stars: Atmospheres
Techniques: radial velocities
Methods: data analysis
Techniques: photometric
Author
S. Sulis
Laboratoire d'Astrophysique de Marseille
M. Lendl
University of Geneva
H. M. Cegla
The University of Warwick
L. F. Rodríguez Díaz
Aarhus University
L. Bigot
Observatoire de la Cote d'Azur
V. Van Grootel
University of Liège
A. Bekkelien
University of Geneva
A. Collier Cameron
University of St Andrews
P. Maxted
Keele University
A.E. Simon
University of Bern
C. Lovis
University of Geneva
Gaetano Scandariato
Istituto nazionale di astrofisica (INAF)
G. Bruno
Istituto nazionale di astrofisica (INAF)
D. Nardiello
Istituto nazionale di astrofisica (INAF)
A. Bonfanti
Institut fur Weltraumforschung
Malcolm Fridlund
Leiden University
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Carina Persson
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
S. Salmon
University of Geneva
S. G. Sousa
University of Porto
T. G. Wilson
University of St Andrews
A. Krenn
University of Geneva
Institut fur Weltraumforschung
S. Hoyer
Laboratoire d'Astrophysique de Marseille
A. Santerne
Laboratoire d'Astrophysique de Marseille
D. Ehrenreich
University of Geneva
Y. Alibert
University of Bern
R. Alonso
Instituto de Astrofísica de Canarias
University of La Laguna
G. Anglada
Institute of Space Studies of Catalonia (IEEC)
Institute of Space Sciences (ICE) - CSIC
T. Bárczy
Admatis
D. Barrado
Centro de Astrobiologia (CAB)
S. C.C. Barros
University of Porto
W. Baumjohann
Institut fur Weltraumforschung
M. Beck
University of Geneva
T. Beck
University of Bern
W. Benz
University of Bern
N. Billot
University of Geneva
X. Bonfils
Institut de Planétologie et d’Astrophysique de Grenoble (IPAG)
L. Borsato
Istituto nazionale di astrofisica (INAF)
A. Brandeker
Stockholm University
C. Broeg
University of Bern
J. Cabrera
German Aerospace Center (DLR)
S. Charnoz
Institut de Physique du Globe de Paris
C. Corral Van Damme
European Space Research and Technology Centre (ESA ESTEC)
Szilard Csizmadia
German Aerospace Center (DLR)
M. B. Davies
Lund University
M. Deleuil
Laboratoire d'Astrophysique de Marseille
A. Deline
University of Geneva
L. Delrez
University of Liège
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
D. Gandolfi
University of Turin
Michaël Gillon
University of Liège
M. Gudel
University of Vienna
Kevin Heng
University of Bern
The University of Warwick
K. Isaak
European Space Research and Technology Centre (ESA ESTEC)
L.L. Kiss
Eötvös Loránd University (ELTE)
Hungarian Academy of Sciences
J. Laskar
Paris Observatory
A. L. des Etangs
Institut d 'Astrophysique de Paris
D. Magrin
Istituto nazionale di astrofisica (INAF)
M. Munari
Istituto nazionale di astrofisica (INAF)
Valerio Nascimbeni
Istituto nazionale di astrofisica (INAF)
G. Olofsson
Stockholm University
R. Ottensamer
University of Vienna
I. Pagano
Istituto nazionale di astrofisica (INAF)
E. Palle
Instituto de Astrofísica de Canarias
G. Peter
German Aerospace Center (DLR)
Giampaolo P. Piotto
Istituto nazionale di astrofisica (INAF)
University of Padua
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)
H. Rauer
German Aerospace Center (DLR)
Technische Universität Berlin
Freie Universität Berlin
I. Ribas
Institute of Space Sciences (ICE) - CSIC
Institute of Space Studies of Catalonia (IEEC)
M. Rieder
University of Bern
N. C. Santos
University of Porto
D. Segransan
University of Geneva
A. M.S. Smith
German Aerospace Center (DLR)
M. Steinberger
Institut fur Weltraumforschung
Manfred B. Steller
Institut fur Weltraumforschung
Gy M. Szabó
Eötvös Loránd University (ELTE)
N. Thomas
University of Bern
S. Udry
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. 670 A24Subject Categories
Astronomy, Astrophysics and Cosmology
Bioinformatics (Computational Biology)
Probability Theory and Statistics
DOI
10.1051/0004-6361/202244223