학술논문
Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076
Document Type
Working Paper
Author
Osborn, Hugh P.; Bonfanti, Andrea; Gandolfi, Davide; Hedges, Christina; Leleu, Adrien; Fortier, Andrea; Futyan, David; Gutermann, Pascal; Maxted, Pierre F. L.; Borsato, Luca; Collins, Karen A.; da Silva, J. Gomes; Chew, Yilen Gómez Maqueo; Hooton, Matthew J.; Lendl, Monika; Parviainen, Hannu; Salmon, Sébastien; Schanche, Nicole; Serrano, Luisa M.; Sousa, Sergio G.; Tuson, Amy; Ulmer-Moll, Solène; Van Grootel, Valerie; Wells, R. D.; Wilson, Thomas G.; Alibert, Yann; Alonso, Roi; Anglada, Guillem; Asquier, Joel; Navascues, David Barrado y; Baumjohann, Wolfgang; Beck, Thomas; Benz, Willy; Biondi, Federico; Bonfils, Xavier; Bouchy, Francois; Brandeker, Alexis; Broeg, Christopher; Bárczy, Tamas; Barros, S. C. C.; Cabrera, Juan; Charnoz, Sébastien; Cameron, Andrew Collier; Csizmadia, Szilard; Davies, Melvyn B.; Deleuil, Magali; Delrez, Laetitia; Demory, Brice-Olivier; Ehrenreich, David; Erikson, Anders; Fossati, Luca; Fridlund, Malcolm; Gillon, Michaël; Gómez-Muñoz, M. A.; Güdel, Manuel; Heng, Kevin; Hoyer, Sergio; Isaak, Kate G.; Kiss, Laszlo; Laskar, Jacques; Etangs, Alain Lecavelier des; Lovis, Christophe; Magrin, Demetrio; Malavolta, Luca; McCormac, James; Nascimbeni, Valerio; Olofsson, Göran; Ottensamer, Roland; Pagano, Isabella; Pallé, Enric; Peter, Gisbert; Piazza, Daniele; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Ragazzoni, Roberto; Rando, Nicola; Rauer, Heike; Reimers, Christian; Ribas, Ignasi; Demangeon, Olivier D. S.; Smith, Alexis M. S.; Sabin, L.; Santos, Nuno; Scandariato, Gaetano; Schroffenegger, U.; Schwarz, Rick P.; Shporer, Avi; Simon, Attila E.; Steller, Manfred; Szabó, Gyula M.; Ségransan, Damien; Thomas, Nicolas; Udry, Stéphane; Walter, Ingo; Walton, Nicholas
Source
A&A 664, A156 (2022)
Subject
Language
Abstract
Context: TOI-2076 is a transiting three-planet system of sub-Neptunes orbiting a bright (G = 8.9 mag), young ($340\pm80$ 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 $P=21.01538^{+0.00084}_{-0.00074}$ 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 $P=35.12537\pm0.00067$ d alias. These observations also improved the radius precision of all three sub-Neptunes to $2.518\pm0.036$, $3.497\pm0.043$, and $3.232\pm0.063$ $R_\oplus$. 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.
Comment: 18 pages, 7 figure, 8 tables. Accepted for publication in Astronomy & Astrophysics. Photometry available on CDS/Vizier. Python package presented for modelling duotransiting planet candidates available at https://github.com/hposborn/MonoTools. Modelling & figure-creation code available at https://github.com/hposborn/TOI2076
Comment: 18 pages, 7 figure, 8 tables. Accepted for publication in Astronomy & Astrophysics. Photometry available on CDS/Vizier. Python package presented for modelling duotransiting planet candidates available at https://github.com/hposborn/MonoTools. Modelling & figure-creation code available at https://github.com/hposborn/TOI2076