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arXiv · 1910.05282

NGTS and WASP photometric recovery of a single-transit candidate from TESS

Samuel Gill·Daniel Bayliss·Benjamin F. Cooke·Peter J. Wheatley·Louise D. Nielsen·Monika Lendl·James McCormac·Edward M. Bryant·Jack S. Acton·David R. Anderson·Claudia Belardi·Francois Bouchy·Matthew R. Burleigh·Andrew Collier-Cameron·Sarah L. Casewell·Michael R. Goad·Maximilian N. Gunther·Coel Hellier·James A. G. Jackman·James S. Jenkins·Maximiliano Moyano·Don Pollacco·Liam Raynard·Alexis M. S. Smith·Rosanna H. Tilbrook·Oliver Turner·Stephane Udry·Richard G. West
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Abstract

The Transiting Exoplanet Survey Satellite (\tess) produces a large number of single-transit event candidates, since the mission monitors most stars for only $\sim$27\,days. Such candidates correspond to long-period planets or eclipsing binaries. Using the \tess\ Sector 1 full-frame images, we identified a 7750\,ppm single-transit event with a duration of 7\,hours around the moderately evolved F-dwarf star \tic\ (Tmag=10.23, \teff=6280$\pm{85}$\,K). Using archival WASP photometry we constrained the true orbital period to one of three possible values. We detected a subsequent transit-event with NGTS, which revealed the orbital period to be 38.20\,d. Radial velocity measurements from the CORALIE Spectrograph show the secondary object has a mass of $M_2$= $0.148\pm{0.003}$\,M$_{\odot}$, indicating this system is an F-M eclipsing binary. The radius of the M-dwarf companion is $R_2$ = $0.171\pm{0.003}$\,R$_{\odot}$, making this one of the most well characterised stars in this mass regime. We find that its radius is 2.3-$\sigma$ lower than expected from stellar evolution models.

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Samuel Gill, Daniel Bayliss, Benjamin F. Cooke, Peter J. Wheatley, Louise D. Nielsen, Monika Lendl, James McCormac, Edward M. Bryant, Jack S. Acton, David R. Anderson, Claudia Belardi, Francois Bouchy, Matthew R. Burleigh, Andrew Collier-Cameron, Sarah L. Casewell, Michael R. Goad, Maximilian N. Gunther, Coel Hellier, James A. G. Jackman, James S. Jenkins, Maximiliano Moyano, Don Pollacco, Liam Raynard, Alexis M. S. Smith, Rosanna H. Tilbrook, Oliver Turner, Stephane Udry, Richard G. West. 2019-10-11. NGTS and WASP photometric recovery of a single-transit candidate from TESS. https://doi.org/10.1093/mnras/stz3212

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