Using Limb-Darkening to Measure the Masses of Red Giants

TL;DR

This paper introduces a new method to determine the masses of red giant stars by analyzing their limb-darkening profiles, linking the limb-darkening coefficients to the stellar radius-to-mass ratio, and applying it to a microlensing event.

Contribution

The paper develops a novel approach connecting limb-darkening coefficients to stellar mass, enabling mass measurement of evolved stars through limb-darkening observations.

Findings

Limb-darkening coefficients relate to the R/M ratio.

Application to microlensing event EROS-BLG-2000-5 demonstrates method viability.

The method provides a new way to measure stellar masses.

Abstract

We present a novel method for measuring the masses of evolved stars from their limb-darkening observations parameterized as a linear-plus-square-root function with two coefficients. The coefficients of the law are related to integrated moments of the intensity and carry information about the extension of the stellar atmosphere, which is correlated to the ratio of the stellar radius to mass, R/M. Here, we show why the limb-darkening law is related to the R/M, and apply this result to limb-darkening observations of the microlensing event EROS-BLG-2000-5.