Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Osborn, HP (Author) Other; Bonfanti, A (Author) Other; Gandolfi, D (Author) Other; Hedges, C (Author) Other; Leleu, A (Author) Other; Fortier, A (Author) Other; Futyan, D (Author) Other; Gutermann, P (Author) Other; Maxted, PFL (Author) Other; Borsato, L (Author) Other; Collins, KA (Author) Other; da Silva, JG (Author) Other; Chew, YGM (Author) Other; Hooton, MJ (Author) Other; Lendl, M (Author) Other; Parviainen, H (Author) Other; Salmon, S (Author) Other; Schanche, N (Author) Other; Serrano, LM (Author) Other; Sousa, SG (Author) FCUP; Tuson, A (Author) Other; Ulmer Moll, S (Author) Other; Van Grootel, V (Author) Other; Wells, RD (Author) Other; Wilson, TG (Author) Other; Alibert, Y (Author) Other; Alonso, R (Author) Other; Anglada, G (Author) Other; Asquier, J (Author) Other; Navascues, DBY (Author) Other; Baumjohann, W (Author) Other; Beck, T (Author) Other; Benz, W (Author) Other; Biondi, F (Author) Other; Bonfils, X (Author) Other; Bouchy, F (Author) Other; Brandeker, A (Author) Other; Broeg, C (Author) Other; Barczy, T (Author) Other; Barros, SCC (Author) FCUP; Cabrera, J (Author) Other; Charnoz, S (Author) Other; Cameron, AC (Author) Other; Csizmadia, S (Author) Other; Davies, MB (Author) Other; Deleuil, M (Author) Other; Delrez, L (Author) Other; Demory, BO (Author) Other; Ehrenreich, D (Author) Other; Erikson, A (Author) Other; Fossati, L (Author) Other; Fridlund, M (Author) Other; Gillon, M (Author) Other; Gomez Munoz, MA (Author) Other; Gudel, M (Author) Other; Heng, K (Author) Other; Hoyer, S (Author) Other; Isaak, KG (Author) Other; Kiss, L (Author) Other; Laskar, J (Author) Other; des Etangs, AL (Author) Other; Lovis, C (Author) Other; Magrin, D (Author) Other; Malavolta, L (Author) Other; McCormac, J (Author) Other; Nascimbeni, V (Author) Other; Olofsson, G (Author) Other; Ottensamer, R (Author) Other; Pagano, I (Author) Other; Palle, E (Author) Other; Peter, G (Author) Other; Piazza, D (Author) Other; Piotto, G (Author) Other; Pollacco, D (Author) Other; Queloz, D (Author) Other; Ragazzoni, R (Author) Other; Rando, N (Author) Other; Rauer, H (Author) Other; Reimers, C (Author) Other; Ribas, I (Author) Other; Demangeon, ODS (Author) Other; Smith, AMS (Author) Other; Sabin, L (Author) Other; N.C. Santos (Author) FCUP; Scandariato, G (Author) Other; Schroffenegger, U (Author) Other; Schwarz, RP (Author) Other; Shporer, A (Author) Other; Simon, AE (Author) Other; Steller, M (Author) Other; Szabo, GM (Author) Other; Segransan, D (Author) Other; Thomas, N (Author) Other; Udry, S (Author) Other; Walter, I (Author) Other; Walton, N (Author) Other

Journal

Title: Astronomy and Astrophysics

Vol. 664

Final page: A156

ISSN: 0004-6361

Publisher: EDP Sciences

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 5 Citations

Other information

Authenticus ID: P-00X-5W5

DOI: 10.1051/0004-6361/202243065

Abstract (EN): Context. TOI-2076 is a transiting three-planet system of sub-Neptunes orbiting a bright (G = 8.9 mag), young (340 +/- 80 Myr) K-type star. Although a validated planetary system, the orbits of the two outer planets were unconstrained as only two non-consecutive transits were seen in TESS photometry. This left 11 and 7 possible period aliases for each. Aims. To reveal the true orbits of these two long-period planets, precise photometry targeted on the highest-probability period aliases is required. Long-term monitoring of transits in multi-planet systems can also help constrain planetary masses through TTV measurements. Methods. We used the MonoTools package to determine which aliases to follow, and then performed space-based and ground-based photometric follow-up of TOI-2076 c and d with CHEOPS, SAINT-EX, and LCO telescopes. Results. CHEOPS observations revealed a clear detection for TOI-2076 c at P = 21.01538(-0.00074)(+0.00084) d, and allowed us to rule out three of the most likely period aliases for TOI-2076 d. Ground-based photometry further enabled us to rule out remaining aliases and confirm the P = 35.12537 +/- 0.00067 d alias. These observations also improved the radius precision of all three sub-Neptunes to 2.518 +/- 0.036, 3.497 +/- 0.043, and 3.232 +/- 0.063 R-circle plus. Our observations also revealed a clear anti-correlated TTV signal between planets b and c likely caused by their proximity to the 2:1 resonance, while planets c and d appear close to a 5:3 period commensurability, although model degeneracy meant we were unable to retrieve robust TTV masses. Their inflated radii, likely due to extended H-He atmospheres, combined with low insolation makes all three planets excellent candidates for future comparative transmission spectroscopy with JWST.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 17