An Estimate of the Yield of Single-transit Planetary Events from the Transiting Exoplanet Survey Satellite

Abstract

Abstract We present a semianalytic estimate of the expected yield of single-transit planets from the Transiting Exoplanet Survey Satellite (TESS). We use the TESS Candidate Target List-6 (CTL-6) as an input catalog of over four million sources. We predict that from the 200,000 stars selected to be observed with the high-cadence postage stamps (PSs) with the highest CTL-6 priority, there will be 241 single-transit events caused by planets detectable at a signal-to-noise ratio of S/N ≥ 7.3. We find a lower limit of an additional 977 events caused by single-transit planets in the full frame images (FFIs); this is a lower limit because the CTL-6 is incomplete below a TESS magnitude of . Of the single-transit events from the PSs and FFIs, 1091/1218 will have transit depths deeper than 0.1% and will thus be amenable for photometric follow-up from the ground, and 1195/1218 will have radial velocity signals greater than 1 m s−1. We estimate that the periods of 146 single transits will be constrained to better than 10% using the TESS photometry assuming circular orbits. We find that the number of planets detected by TESS in the PSs with periods days can be doubled by including single-transiting planets, while the number of planets with days can be increased by an order of magnitude. We predict 79 habitable zone planets in the TESS light curves from single transits, with 18 orbiting FGK stars.