The EBLM Project– XI. Mass, radius, and effective temperature measurements for 23 M-dwarf companions to solar-type stars observed with CHEOPS

Autor(en)

M. I. Swayne, P. F.L. Maxted, A. H.M.J. Triaud, S. G. Sousa, A. Deline, D. Ehrenreich, S. Hoyer, G. Olofsson, I. Boisse, A. Duck, S. Gill, D. Martin, J. McCormac, C. M. Persson, A. Santerne, D. Sebastian, M. R. Standing, L. Acuña, Y. Alibert, R. Alonso, G. Anglada, T. Bárczy, D. Barrado Navascues, S. C.C. Barros, W. Baumjohann, T. A. Baycroft, M. Beck, T. Beck, W. Benz, N. Billot, X. Bonfils, L. Borsato, V. Bourrier, A. Brandeker, C. Broeg, A. Carmona, S. Charnoz, A. Collier Cameron, P. Cortés-Zuleta, Sz Csizmadia, P. E. Cubillos, M. B. Davies, M. Deleuil, X. Delfosse, L. Delrez, O. D.S. Demangeon, B. O. Demory, G. Dransfield, A. Erikson, A. Fortier, T. Forveille, L. Fossati, M. Fridlund, D. Gandolfi, M. Gillon, M. Güdel, M. N. Günther, N. Hara, G. Hébrard, N. Heidari, C. Hellier, Ch Helling, K. G. Isaak, F. Kerschbaum, F. Kiefer, L. L. Kiss, V. Kunovac, S. Lalitha, K. W.F. Lam, J. Laskar, A. Lecavelier des Etangs, M. Lendl, D. Magrin, L. Marafatto, E. Martioli, N. J. Miller, C. Mordasini, C. Moutou, V. Nascimbeni, R. Ottensamer, I. Pagano, E. Pallé, G. Peter, D. Piazza, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni, N. Rando, H. Rauer, I. Ribas, N. C. Santos, G. Scandariato, D. Ségransan, A. E. Simon, A. M.S. Smith, R. Southworth, M. Stalport, Gy M. Szabó, N. Thomas, S. Udry, B. Ulmer, V. Van Grootel, J. Venturini, N. A. Walton, E. Willett, T. G. Wilson

Abstrakt

Observations of low-mass stars have frequently shown a disagreement between observed stellar radii and radii predicted by theoretical stellar structure models. This ‘radius inflation’ problem could have an impact on both stellar and exoplanetary science. We present the final results of our observation programme with the CHaracterising ExOPlanet Satellite (CHEOPS) to obtain high-precision light curves of eclipsing binaries with low-mass stellar companions (EBLMs). Combined with the spectroscopic orbits of the solar-type companions, we can derive the masses, radii, and effective temperatures of 23 M-dwarf stars. We use the PYCHEOPS data analysis software to analyse their primary and secondary occultations. For all but one target, we also perform analyses with Transiting Exoplanet Survey Satellite (TESS) light curves for comparison. We have assessed the impact of starspot-induced variation on our derived parameters and account for this in our radius and effective temperature uncertainties using simulated light curves. We observe trends in inflation with both metallicity and orbital separation. We also observe a strong trend in the difference between theoretical and observational effective temperatures with metallicity. There is no such trend with orbital separation. These results are not consistent with the idea that the observed inflation in stellar radius combines with lower effective temperature to preserve the luminosity predicted by low-mass stellar models. Our EBLM systems provide high-quality and homogeneous measurements that can be used in further studies of radius inflation.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Keele University, University of Birmingham, Universidade do Porto, Universität Genf, Aix-Marseille Université, Stockholm University, Tufts University, University of Warwick, Chalmers University of Technology, Open University, Universität Bern, 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), Österreichische Akademie der Wissenschaften (ÖAW), Université Grenoble-Alpes, INAF - Osservatorio Astronomico di Padova, Université de Paris, University of St. Andrews, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), INAF-Osservatorio Astrofisico di Torino, Lund University, Université de Liège, Leiden University, Università degli Studi di Torino, European Space Research & Technology Centre (ESA/ESTEC), Université Paris VI - Pierre-et-Marie-Curie, Centre National De La Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur, Technische Universität Graz, Université de recherche Paris Sciences et Lettres, MTA Társadalomtudományi Kutatóközpont, Eötvös Loránd University Budapest, Laboratório Nacional de Astrofísica, Polish Academy of Sciences (PAS), Université de Toulouse, INAF-Osservatorio Astrofisico di Catania, Università degli Studi di Padova, Eidgenössische Technische Hochschule Zürich, University of Cambridge, Technische Universität Berlin, Freie Universität Berlin (FU), HUN-REN-ELTE Exoplanet Research Group

Journal

Monthly Notices of the Royal Astronomical Society

Band

528

Seiten

5703-5722

Anzahl der Seiten

20

ISSN

0035-8711

DOI

https://doi.org/10.1093/mnras/stad3866

Publikationsdatum

03-2024

Peer-reviewed

Ja

ÖFOS 2012

103003 Astronomie, 103004 Astrophysik, 103038 Weltraumforschung

Schlagwörter

ASJC Scopus Sachgebiete

Astronomy and Astrophysics, Space and Planetary Science

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/7c358e8e-fa87-4cb1-ae94-4f02553118ba