TOI-836: A super-Earth and mini-Neptune transiting a nearby K-dwarf. Issue 3 (9th February 2023)

• Record Type: Journal Article
• Authors: Hawthorn, Faith; Bayliss, Daniel; Wilson, Thomas G; Bonfanti, Andrea; Adibekyan, Vardan; Alibert, Yann; Sousa, Sérgio G; Collins, Karen A; Bryant, Edward M; Osborn, Ares; Armstrong, David J; Abe, Lyu; Acton, Jack S; Addison, Brett C; Agabi, Karim; Alonso, Roi; Alves, Douglas R; Anglada-Escudé, Guillem; Bárczy, Tamas; Barclay, Thomas; Barrado, David; Barros, Susana C C; Baumjohann, Wolfgang; Bendjoya, Philippe; Benz, Willy; Bieryla, Allyson; Bonfils, Xavier; Bouchy, François; Brandeker, Alexis; Broeg, Christopher; Brown, David J A; Burleigh, Matthew R; Buttu, Marco; Cabrera, Juan; Caldwell, Douglas A; Casewell, Sarah L; Charbonneau, David; Charnoz, Sébastian; Cloutier, Ryan; Cameron, Andrew Collier; Collins, Kevin I; Conti, Dennis M; Crouzet, Nicolas; Czismadia, Szilárd; Davies, Melvyn B; Deleuil, Magali; Delgado-Mena, Elisa; Delrez, Laetitia; Demangeon, Olivier D S; Demory, Brice-Olivier; Dransfield, Georgina; Dumusque, Xavier; Egger, Jo Ann; Ehrenreich, David; Eigmüller, Philipp; Erickson, Anders; Essack, Zahra; Fortier, Andrea; Fossati, Luca; Fridlund, Malcolm; Günther, Maximilian N; Güdel, Manuel; Gandolfi, Davide; Gillard, Harvey; Gillon, Michaël; Gnilka, Crystal; Goad, Michael R; Goeke, Robert F; Guillot, Tristan; Hadjigeorghiou, Andreas; Hellier, Coel; Henderson, Beth A; Heng, Kevin; Hooton, Matthew J; Horne, Keith; Howell, Steve B; Hoyer, Sergio; Irwin, Jonathan M; Jenkins, James S; Jenkins, Jon M; Jensen, Eric L N; Kane, Stephen R; Kendall, Alicia; Kielkopf, John F; Kiss, Laszlo L; Lacedelli, Gaia; Laskar, Jacques; Latham, David W; Etangs, Alain Lecavalier des; Leleu, Adrien; Lendl, Monika; Lillo-Box, Jorge; Lovis, Christophe; Mékarnia, Djamel; Massey, Bob; Masters, Tamzin; Maxted, Pierre F L; Nascimbeni, Valerio; Nielsen, Louise D; O'Brien, Sean M; Olofsson, Göran; Osborn, Hugh P; Pagano, Isabella; Pallé, Enric; Persson, Carina M; Piotto, Giampaolo; Plavchan, Peter; Pollacco, Don; Queloz, Didier; Ragazzoni, Roberto; Rauer, Heike; Ribas, Ignasi; Ricker, George; Ségransan, Damien; Salmon, Sébastien; Santerne, Alexandre; Santos, Nuno C; Scandariato, Gaetano; Schmider, François-Xavier; Schwarz, Richard P; Seager, Sara; Shporer, Avi; Simon, Attila E; Smith, Alexis M S; Srdoc, Gregor; Steller, Manfred; Suarez, Olga; Szabó, Gyula M; Teske, Johanna; Thomas, Nicolas; Tilbrook, Rosanna H; Triaud, Amaury H M J; Udry, Stéphane; Van Grootel, Valérie; Walton, Nicholas; Wang, Sharon X; Wheatley, Peter J; Winn, Joshua N; Wittenmyer, Robert A; Zhang, Hui;
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 520:Issue 3(2023)
• Page Start: 3649
• Page End: 3668
• Publication Date: 2023-02-09
• Subjects: techniques: photometric -- techniques: radial velocities -- planets and satellites: detection -- stars: individual: TOI-836 (TIC 440887364, GAIA EDR3 6230733559097425152); Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stad306
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and Sector 38. TOI-836 is a bright ( T = 8.5 mag), high proper motion (∼200 mas yr −1 ), low metallicity ([Fe/H]≈−0.28) K-dwarf with a mass of 0.68 ± 0.05 M⊙ and a radius of 0.67 ± 0.01 R⊙ . We obtain photometric follow-up observations with a variety of facilities, and we use these data sets to determine that the inner planet, TOI-836 b, is a 1.70 ± 0.07 R⊕ super-Earth in a 3.82-d orbit, placing it directly within the so-called 'radius valley'. The outer planet, TOI-836 c, is a 2.59 ± 0.09 R⊕ mini-Neptune in an 8.60-d orbit. Radial velocity measurements reveal that TOI-836 b has a mass of 4.5 ± 0.9 M⊕, while TOI-836 c has a mass of 9.6 ± 2.6 M⊕ . Photometric observations show Transit Timing Variations (TTVs) on the order of 20 min for TOI-836 c, although there are no detectable TTVs for TOI-836 b. The TTVs of planet TOI-836 c may be caused by an undetected exterior planet.