paper

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

arXiv:1910.05282 · doi:10.1093/mnras/stz3212

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 $_{⊙}$ , 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 $_{⊙}$ , making this one of the most well characterised stars in this mass regime. We find that its radius is 2.3- $I ¨ $ lower than expected from stellar evolution models.

6 pages, 5 Figures, 1 Table. Submitted to MNRAS letters