Convection in Cool Stars, as Seen Through Kepler's Eyes

TL;DR

This paper explores how Kepler's high-precision photometry reveals stellar surface convection through light curve flicker, providing a new method to measure surface gravity and improve exoplanet detection and understanding of stellar evolution.

Contribution

It introduces the concept of using light curve flicker as a diagnostic for surface convection and surface gravity, expanding the tools for stellar and exoplanet studies.

Findings

Flicker correlates with surface gravity with ~0.1 dex precision.

Flicker can improve exoplanet property estimation.

Flicker offers insights into stellar evolution.

Abstract

Stellar surface processes represent a fundamental limit to the detection of extrasolar planets with the currently most heavily-used techniques. As such, considerable effort has gone into trying to mitigate the impact of these processes on planet detection, with most studies focusing on magnetic spots. Meanwhile, high-precision photometric planet surveys like CoRoT and Kepler have unveiled a wide variety of stellar variability at previously inaccessible levels. We demonstrate that these newly revealed variations are not solely magnetically driven but also trace surface convection through light curve "flicker." We show that "flicker" not only yields a simple measurement of surface gravity with a precision of ~0.1 dex, but it may also improve our knowledge of planet properties, enhance radial velocity planet detection and discovery, and provide new insights into stellar evolution.