Searching for Giant Exoplanets Around M-dwarf Stars (GEMS) I: Survey Motivation

Recent discoveries of transiting giant exoplanets around M-dwarf stars(GEMS), aided by the all-sky coverage of TESS, are starting to stretch theoriesof planet formation through the core-accretion scenario. Recent upper limits ontheir occurrence suggest that they decrease with lower stellar masses, withfewer GEMS around lower-mass stars compared to solar-type. In this paper, wediscuss existing GEMS both through confirmed planets, as well as protoplanetarydisk observations, and a combination of tests to reconcile these withtheoretical predictions. We then introduce the Searching for GEMSsurvey, where we utilize multi-dimensional nonparameteric statistics tosimulate hypothetical survey scenarios to predict the required sample size oftransiting GEMS with mass measurements to robustly compare their bulk-densitywith canonical hot-Jupiters orbiting FGK stars. Our Monte-Carlo simulationspredict that a robust comparison requires about 40 transiting GEMS (compared tothe existing sample of ∼ 15) with 5-σ mass measurements.Furthermore, we discuss the limitations of existing occurrence estimates forGEMS, and provide a brief description of our planned systematic search toimprove the occurrence rate estimates for GEMS.