The Effect of Stellar Rotation on Apparent Bolometric Luminosity

Abstract

The change in apparent bolometric magnitude of a rotating star with orientation of the polar axis with respect to the line of sight is studied for varying values of the angular velocity. The behaviour of a given mass under all allowable angular velocities is considered, assuming a homogeneous model, von Zeipel's theorem, and independence of volume upon rotation. Comparisons are made with previously published results based on the Roche model. It is shown that the results differ when the assumption of rotational invariance of mass and volume is replaced by the assumption of rotational invariance of the total luminosity and polar radius.