Discovery of TOI-1260d and the characterization of the multiplanet system

Author(s)
K. W.F. Lam, J. Cabrera, M. J. Hooton, Y. Alibert, A. Bonfanti, M. Beck, A. Deline, H. G. Floren, A. E. Simon, L. Fossati, C. M. Persson, M. Fridlund, S. Salmon, S. Hoyer, H. P. Osborn, T. G. Wilson, I. Y. Georgieva, Gr Nowak, R. Luque, J. A. Egger, V. Adibekyan, R. Alonso, G. A. Escude, T. Bárczy, D. Barrado, S. C.C. Barros, W. Baumjohann, T. Beck, A. Bekkelien, W. Benz, N. Billot, X. Bonfils, A. Brandeker, C. Broeg, S. Charnoz, A. C. Cameron, Sz Csizmadia, M. B. Davies, M. Deleuil, L. Delrez, O. D.S. Demangeon, B. O. Demory, D. Ehrenreich, A. Erikson, A. Fortier, D. Futyan, D. Gandolfi, M. Gillon, M. Guedel, P. Guterman, J. Laskar, D. W. Latham, A. Lecavelier Des Etangs, M. Lendl, C. Lovis, K. Heng, K. G. Isaak, L. Kiss, D. Magrin, P. F.L. Maxted, V. Nascimbeni, G. Olofsson, R. Ottensamer, I. Pagano, E. Palle, G. Peter, G. Piotto, D. Pollacco, D. Queloz, I. Ribas, R. Ragazzoni, N. Rando, H. Rauer, N. C. Santos, G. Scandariato, S. Seager, D. Segransan, L. M. Serrano, A. M.S. Smith, S. G. Sousa, M. Steller, G. M. Szabó, N. Thomas, S. Udry, V. Van Grootel, N. A. Walton, J. N. Winn
Abstract

We report the discovery of a third planet transiting the star TOI-1260, previously known to host two transiting sub-Neptune planets with orbital periods of 3.127 and 7.493 d, respectively. The nature of the third transiting planet with a 16.6-d orbit is supported by ground-based follow-up observations, including time-series photometry, high-angular resolution images, spectroscopy, and archival imagery. Precise photometric monitoring with CHEOPS allows to improve the constraints on the parameters of the system, improving our knowledge on their composition. The improved radii of TOI-1260b and TOI-1260c are 2.36 ± 0.06 R⊕, 2.82 ± 0.08 R⊕ , respectively while the newly discovered third planet has a radius of 3.09 ± 0.09 R⊕. The radius uncertainties are in the range of 3 per cent, allowing a precise interpretation of the interior structure of the three planets. Our planet interior composition model suggests that all three planets in the TOI-1260 system contains some fraction of gas. The innermost planet TOI-1260b has most likely lost all of its primordial hydrogen-dominated envelope. Planets c and d were also likely to have experienced significant loss of atmospheric through escape, but to a lesser extent compared to planet b.

Organisation(s)
Department of Astrophysics
External organisation(s)
Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Universität Bern, University of Cambridge, Österreichische Akademie der Wissenschaften (ÖAW), Université de Genève, Stockholm University, Leiden University, Aix-Marseille Université, Massachusetts Institute of Technology, University of St. Andrews, Institute of Astrophysics of the Canary Islands, University of La Laguna, University of Chicago, Universidade do Porto, Universitat Autònoma de Barcelona , Spanish National Research Council (CSIC), Institute of Space Studies of Catalonia (IEEC), Admatis Ltd., European Space Astronomy Centre (ESA), University of Grenoble Alpes, Université de Paris, Lund University, Université de Liège, Università degli Studi di Torino, Institute National Des Sciences De L'univers Division Technique, Université de recherche Paris Sciences et Lettres, Harvard-Smithsonian Center for Astrophysics, Université Paris VI - Pierre-et-Marie-Curie, University of Warwick, Science and Operations Department - Science Division (SCI-SC), Eötvös Loránd Research Network, Eötvös Loránd University Budapest, The University of Sydney, Osservatorio Astronomico, Keele University, INAF-Osservatorio Astrofisico di Catania, Eidgenössische Technische Hochschule Zürich, University of Padova, Technische Universität Berlin, Freie Universität Berlin (FU), Princeton University
Journal
Monthly Notices of the Royal Astronomical Society
Volume
519
Pages
1437-1451
No. of pages
15
ISSN
0035-8711
DOI
https://doi.org/10.1093/mnras/stac3639
Publication date
02-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics, 103038 Space exploration
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/d81e12d8-4a7c-425b-bc7e-8d27c2eb89c3