Search for exoplanetary transits in the Galactic bulge

Abstract

A search for extrasolar planetary transits using extended Kepler mission (K2) campaigns 9 and 11 revealed five new candidates towards the Galactic bulge. The stars EPIC 224439122, 224560837, 227560005, 230778501 and 231635524 are found to have low-amplitude transits consistent with extrasolar planets, with periods P = 35.1695, 3.6390, 12.4224, 17.9856 and 5.8824 days, respectively. The K2 data and existing optical photometry are combined with multi-band near-IR photometry of the Vista Variables in the Via Lactea (VVV) survey and Two-Micron All-Sky Survey (2MASS) in order to measure accurate physical parameters for the host stars. We then measure the radii of the new planet candidates from the K2 transit light curves and also estimate their masses using mass-radius relations, concluding that two of these candidates could be low-mass planets and three could be giant gaseous planets.