Connecting photometric and spectroscopic granulation signals with CHEOPS and ESPRESSO

Autor(en)
S. Sulis, M. Lendl, H. M. Cegla, L. F. Rodríguez Díaz, L. Bigot, V. Van Grootel, A. Bekkelien, A. Collier Cameron, P. F.L. Maxted, A. E. Simon, C. Lovis, G. Scandariato, G. Bruno, D. Nardiello, A. Bonfanti, M. Fridlund, C. M. Persson, S. Salmon, S. G. Sousa, T. G. Wilson, A. Krenn, S. Hoyer, A. Santerne, D. Ehrenreich, Y. Alibert, R. Alonso, G. Anglada, T. Bárczy, D. Barrado Y Navascues, S. C.C. Barros, W. Baumjohann, M. Beck, T. Beck, W. Benz, N. Billot, X. Bonfils, L. Borsato, A. Brandeker, C. Broeg, J. Cabrera, S. Charnoz, C. Corral Van Damme, Sz Csizmadia, M. B. Davies, M. Deleuil, A. Deline, L. Delrez, O. D.S. Demangeon, B. O. Demory, A. Erikson, A. Fortier, L. Fossati, D. Gandolfi, M. Gillon, M. Güdel, K. Heng, K. G. Isaak, L. L. Kiss, J. Laskar, A. Lecavelier Des Etangs, D. Magrin, M. Munari, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, E. Pallé, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, M. Rieder, N. C. Santos, D. Ségransan, A. M.S. Smith, M. Steinberger, M. Steller, Gy M. Szabó, N. Thomas, S. Udry, N. A. Walton, D. Wolter
Abstrakt

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.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
Aix-Marseille Université, Universität Genf, University of Warwick, Aarhus University, Observatoire de la Cote da Azur, Université Côte d'Azur, Université de Liège, University of St. Andrews, Keele University, Universität Bern, INAF-Osservatorio Astrofisico di Catania, INAF - Osservatorio Astronomico di Padova, Österreichische Akademie der Wissenschaften (ÖAW), Leiden University, Chalmers University of Technology, Universidade do Porto, Instituto de Astrofísica de Canarias (IAC), Universidad de La Laguna, Spanish National Research Council (CSIC), Institut d'Estudis Espacials de Catalunya (IEEC), Admatis, European Space Astronomy Centre (ESA), Université Grenoble-Alpes, Stockholm University, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Université de Paris, European Space Research & Technology Centre (ESA/ESTEC), Lund University, Università degli Studi di Torino, MTA Társadalomtudományi Kutatóközpont, Eötvös Loránd University Budapest, Université de recherche Paris Sciences et Lettres, Université Paris VI - Pierre-et-Marie-Curie, Università degli Studi di Padova, Eidgenössische Technische Hochschule Zürich, University of Cambridge, Technische Universität Berlin, Freie Universität Berlin (FU), Universitat Autònoma de Barcelona
Journal
Astronomy and Astrophysics
Band
670
Anzahl der Seiten
30
ISSN
0004-6361
DOI
https://doi.org/10.1051/0004-6361/202244223
Publikationsdatum
02-2023
Peer-reviewed
Ja
ÖFOS 2012
103003 Astronomie, 103038 Weltraumforschung, 103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Astronomy and Astrophysics, Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/a8d4791e-bbce-44a7-baba-1e6ef2d50e38