Validating Planet Candidates with TESS and Palomar

The Transiting Exoplanet Survey Satellite (TESS) has discovered nearly 7000 planet candidates to date, of which only a few hundred have been confirmed as bona fide planets. Since the light curves of transiting planets should be nearly achromatic, confirmation studies routinely compare multi-color light curves as part of the candidate vetting process. Although these light curves can be more precise than the TESS data, they are typically not incorporated into the calculation of the TESS candidate’s false-positive probability, or the overall probability that a given planet candidate has a non-planetary astrophysical origin. Here, we present high signal-to-noise infrared transit photometry of a sample of representative TESS candidates with shallow transits obtained with the 200-inch Hale Telescope at Palomar Observatory. We develop a modified version of TRICERATOPS, a software package used to confirm transiting planets via statistical analysis of their light curves, in order to quantify the impact of multi-color transit photometry on their false-positive probabilities. Lastly, we discuss the types of TESS candidates that would benefit the most from multi-color observations.