A long-period (P = 61.8 d) M5V dwarf eclipsing a Sun-like star from TESS and NGTS
Jackman, James A. G.; Wheatley, Peter J.; Bayliss, Daniel; Moyano, Maximiliano; Günther, Maximilian N.; Casewell, Sarah L.; Gill, Samuel; Goad, Michael R.; Anderson, David R.; Burleigh, Matthew R.; Jenkins, James S.; Lendl, Monika; McCormac, James; Udry, Stéphane; Vines, Jose I.; West, Richard G.; Smith, Alexis M. S.; Bryant, Edward M.; Watson, Christopher A.; Bouchy, François; Chaushev, Alexander; Nielsen, Louise D.; Osborn, Hugh P.; Raynard, Liam; Pollacco, Don; Acton, Jack S.; Tilbrook, Rosanna H.; Turner, Oliver; Cooke, Benjamin F.; Belardi, Claudia
United Kingdom, Switzerland, Austria, Chile, Germany, United States
Abstract
The Transiting Exoplanet Survey Satellite has produced a large number of single-transit event candidates which are being monitored by the Next Generation Transit Survey (NGTS). We observed a second epoch for the TIC-231005575 system (Tmag = 12.06 and $T_{\rm eff} = 5500 \pm 85\, \mathrm{ K}$ ) with NGTS and a third epoch with Las Cumbres Observatory's telescope in South Africa to constrain the orbital period ( $P = 61.777\, \mathrm{ d}$ ). Subsequent radial velocity measurements with CORALIE revealed the transiting object has a mass of M2 = 0.128 ± 0.003 M⊙, indicating the system is a G-M binary. The radius of the secondary is R2 = 0.154 ± 0.008 R⊙ and is consistent with MESA models of stellar evolution to better than 1σ.