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arXiv · 2002.09311

A long period (P = 61.8-d) M5V dwarf eclipsing a Sun-like star from TESS and NGTS

Samuel Gill·Benjamin F. Cooke·Daniel Bayliss·Louise D. Nielson·Monika Lendl·Peter J. Wheatley·David R. Anderson·Maximiliano Moyano·Edward M. Bryant·Jack S. Acton·Claudia Belardi·Francois Bouchy·Matthew R. Burleigh·Sarah L. Casewell·Alexander Chausev·Michael R. Goad·James A. G. Jackman·James S. Jenkins·James McCormac·Maximilian N. Gunther·Hugh P. Osborn·Don Pollaco·Liam Raynard·Alexis M. S. Smith·Rosanna H. Tillbrook·Oliver Turner·Stephane Udry·Jose I. Vines·Christopher A. Watson·Richard G. West
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Abstract

The Transiting Exoplanet Survey Satellite (TESS) 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, Teff = 5500 +- 85 K) with NGTS and a third epoch with Las Cumbres Observatory's (LCO) telescope in South Africa to constrain the orbital period (P = 61.777 d). Subsequent radial velocity measurements with CORALIE revealed the transiting object has a mass of M2 = 0.128 +- 0.003 M$_\odot$, indicating the system is a G-M binary. The radius of the secondary is R2 = 0.154 +- 0.008 R$_\odot$ and is consistent with models of stellar evolution to better than 1-$\sigma$.

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Samuel Gill, Benjamin F. Cooke, Daniel Bayliss, Louise D. Nielson, Monika Lendl, Peter J. Wheatley, David R. Anderson, Maximiliano Moyano, Edward M. Bryant, Jack S. Acton, Claudia Belardi, Francois Bouchy, Matthew R. Burleigh, Sarah L. Casewell, Alexander Chausev, Michael R. Goad, James A. G. Jackman, James S. Jenkins, James McCormac, Maximilian N. Gunther, Hugh P. Osborn, Don Pollaco, Liam Raynard, Alexis M. S. Smith, Rosanna H. Tillbrook, Oliver Turner, Stephane Udry, Jose I. Vines, Christopher A. Watson, Richard G. West. 2020-02-20. A long period (P = 61.8-d) M5V dwarf eclipsing a Sun-like star from TESS and NGTS. https://doi.org/10.1093/mnras/staa1248

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