Validating TESS Planet Candidates with TRICERATOPS

Validation has played an important role in the discovery of planets detected by TESS. This process of scrutinizing a planet candidate typically involves an analysis of TESS photometry and a combination of different follow-up observations that rule out sources of astrophysical false positives. Despite its usefulness, validation of TESS planet candidates often lacks a robust statistical framework with which to argue for the existence of a planet. We present TRICERATOPS, an easy-to-use tool that resolves this shortcoming using a Bayesian probability calculation. By combining data from TESS and ground-based facilities, our tool quantifies the chance of a transit-like signal originating from both known and unresolved stars located near the potential planet-hosting star on the sky. We display that these quantities reliably predict which candidates are bona fide planets and which candidates are astrophysical false positives, such as nearby eclipsing binaries. We also discuss contexts in which validation with TRICERATOPS is particularly valuable, such as the discovery of planets around stars that make difficult targets for precise radial velocity observations.