K2 light curve for K2-231

The ~81 day light curve for EPIC 219800881 (V=12.71) from K2 Campaign 7 shows six transits with a period of 13.84 days, a depth of ~0.06%, and a duration of ~4hr. Based on our analysis of high-resolution MIKE spectra, broadband optical and NIR photometry, the cluster parallax and interstellar reddening, and isochrone models from PARSEC, Dartmouth, and MIST, we estimate the following properties for the host star: M_*_=1.01+/-0.03M_{sun}_, R_*_=0.95+/-0.03R_{sun}_, and T_eff_=5695+/-50K.

This star appears to be single based on our modeling of the photometry, the low radial velocity (RV) variability measured over nearly 10yr, and Keck/NIRC2 adaptive optics imaging and aperture-masking interferometry. Applying a probabilistic mass-radius relation, we estimate that the mass of this planet is M_p_=7+5-3M_{Earth}_, which would cause an RV semi-amplitude of K=2+/-1m/s that may be measurable with existing precise RV facilities.