Kepler-730 is a planetary system hosting a statistically validated hot Jupiter in a 6.49-day orbit and an additional transiting candidate in a 2.85-day orbit. We use spectroscopic radial velocities from the APOGEE-2N instrument, Robo-AO contrast curves, and Gaia distance estimates to statistically validate the planetary nature of the additional Earth-sized candidate. We perform astrophysical false positive probability calculations for the candidate using the available Kepler data and bolster the statistical validation by using radial velocity data to exclude a family of possible binary star solutions. Using a radius estimate for the primary star derived from stellar models, we compute radii of 1.100−0.050+0.047RJup and 0.140±0.012RJup (1.57±0.13R⊕) for Kepler-730b and Kepler-730c, respectively. Kepler-730 is only the second compact system hosting a hot Jupiter with an inner, transiting planet.
@article{arxiv.1812.08358,
title = {Kepler-730: A hot Jupiter system with a close-in, transiting, Earth-sized planet},
author = {Caleb I. Cañas and Songhu Wang and Suvrath Mahadevan and Chad F. Bender and Nathan De Lee and Scott W. Fleming and D. A. García-Hernández and Fred R. Hearty and Steven R. Majewski and Alexandre Roman-Lopes and Donald P. Schneider and Keivan G. Stassun},
journal= {arXiv preprint arXiv:1812.08358},
year = {2019}
}