Exploring the Dependence of Hot Jupiter Occurrence Rates on Stellar Mass with TESS

TL;DR

This study estimates hot Jupiter occurrence rates around dwarf stars using TESS data, revealing a higher occurrence around lower-mass stars and aligning with Kepler and RV survey results after accounting for stellar multiplicity.

Contribution

It provides the first TESS-based occurrence rates for hot Jupiters across AFG dwarf stars and demonstrates the impact of stellar multiplicity correction on these estimates.

Findings

Hot Jupiter occurrence increases with decreasing stellar mass.

Correcting for stellar binaries aligns transit and RV occurrence rates.

Estimated single-star hot Jupiter rate for G stars is approximately 1%.

Abstract

We present estimates for the occurrence rates of hot Jupiters around dwarf stars based on data from the Transiting Exoplanet Survey Satellite (TESS) Prime Mission. We take 97 hot Jupiters orbiting 198,721 AFG dwarf stars (ranging in mass from $0.8M_{\odot}$ to $2.3M_{\odot}$) from an independent search for hot Jupiters using TESS Prime Mission data. We estimate our planet sample's false positive rates as $14\pm7\%$ for A stars, $16\pm6\%$ for F stars, and $0\%$ for G stars. We find hot Jupiter occurrence rates of $0.29 \pm 0.05\%$ for A stars, $0.36 \pm 0.06\%$ for F stars and $0.55 \pm 0.14\%$ for G stars, with a weighted average across AFG stars of $0.33\pm0.04\%$. Our results show a correlation between higher hot Jupiter abundance and lower stellar mass, and are in good agreement with occurrence rates found by Kepler. After correcting for the presence of binaries in the TESS stellar sample, we estimate a single-star hot Jupiter occurrence rate of $0.98\pm0.36\%$ for G stars. This is in agreement with results from radial velocity (RV) surveys, indicating that stellar multiplicity correction is able to resolve the discrepancy between hot Jupiter occurrence rates based on transits and RVs.