K2-140b – an eccentric 6.57 d transiting hot Jupiter in Virgo

Abstract

We present the discovery of K2-140b, a P = 6.57 d Jupiter-mass (M-P = 1.019 +/- 0.070 M-Jup) planet transiting a V = 12.5 (G5-spectral type) star in an eccentric orbit (e = 0.120(-0.046)(+0.056)) detected using a combination of K2 photometry and ground-based observations. With a radius of 1.095 +/- 0.018 R-Jup, the planet has a bulk density of 0.726 +/- 0.062 rho(Jup). The host star has a [Fe/H] of 0.12 +/- 0.045, and from the K2 light curve, we find a rotation period for the star of 16.3 +/- 0.1 d. This discovery is the 9th hot Jupiter from K2 and highlights K2's ability to detect transiting giant planets at periods slightly longer than traditional, ground- based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters.