A dearth of close-in planets around rapidly rotating stars or a dearth of data?

TL;DR

This study reanalyzed the distribution of close-in planets around stars with different rotation speeds using expanded Kepler and TESS data, finding that previous perceived dearth may be due to limited data rather than an actual scarcity.

Contribution

It provides a more comprehensive analysis showing that the supposed dearth of close-in planets around rapid rotators is likely a data artifact, not a real astrophysical phenomenon.

Findings

The dearth of close-in planets around rapid rotators is not statistically significant.

Expanded data shows similar distributions of close-in planets around both rapid and slow rotators.

Previous observations of scarcity may be due to limited data samples.

Abstract

A dearth of close-in planets orbiting rapid rotators was reported almost a decade ago. According to this view only slowly spinning stars with rotation periods longer than 5-10 days would host planets with orbital periods shorter than 2 or 3 days. This Letter brings an enlarged and more detailed analysis that led us to the question: Is there really a dearth in that distribution or is it a dearth of data? For this new analysis, we combined different samples of Kepler and TESS stars with confirmed planets or planet candidates with measured stellar rotation periods, using Gaia data to perform an in-depth selection of 1013 planet-hosting main-sequence stars. With the newer, enlarged, and more refined data, the reported dearth of close-in planets orbiting rapid rotators tends to disappear, thus suggesting that it may reflect a scarcity of data in the prior analysis. A two sample statistical test strongly supports our results, showing that the distribution of close-in planets orbiting rapid rotators is almost indistinguishable from that for close-in planets orbiting slow rotators.