C © 2015. The American Astronomical Society. All rights reserved. KEPLER-445, KEPLER-446 AND THE OCCURRENCE OF COMPACT MULTIPLES ORBITING MID-M DWARF STARS

We confirm and characterize the exoplanetary systems Kepler-445 and Kepler-446: two mid-M dwarf stars, each with multiple, small, short-period transiting planets. Kepler-445 is a metal-rich ([Fe/H] = +0.25 ± 0.10) M4 dwarf with three transiting planets, and Kepler-446 is a metal-poor ([Fe/H] = −0.30 ± 0.10) M4 dwarf also with three transiting planets. Kepler-445c is similar to GJ 1214b: both in planetary radius and the properties of the host star. The Kepler-446 system is similar to the Kepler-42 system: both are metal-poor with large galactic space velocities and three short-period, likely rocky transiting planets that were initially assigned erroneously large planet-to-star radius ratios. We independently determined stellar parameters from spectroscopy and searched for and fitted the transit light curves for the planets, imposing a strict prior on stellar density in order to remove correlations between the fitted impact parameter and planet-to-star radius ratio for short-duration transits. Combining Kepler-445, Kepler-446, an