Transit timing variations of the exoplanet K2-25b

Abstract

Transit light curves of the exoplanet K2-25b were studied to examine the possibility of transit timing variations (TTVs) in the system, which could imply the presence of a perturbing planet. Observations of K2-25b transits were taken using 14-inch and 24-inch telescopes at Wallace Astrophysical Observatory. Two transit light curves were fit using an MCMC implementation to find the orbital period, planetary radius, and semi-major axis. A new period calculation yielded an orbital period of 3.48457 +/-0.00004, consistent with the period of 3.484552 +0.000044/-0.000036 from Mann et al. 2016. No significant variations were found in the midtimes of the new transit observations when comparing them to the midtime originally published in Mann et al. 2016. Future observations will require smaller uncertainties to meaningfully constrain the mass and period of potential perturbing planets. Signal-to-noise ratio calculations showed that telescopes over approximately 2.2 meters in diameter have better potential to detect small TTVs.