Structure of Uniformly Rotating Stars

TL;DR

This paper models the structure of uniformly rotating stars across various masses and rotation rates, highlighting the importance of surface shape as a key parameter for understanding stellar rotation effects.

Contribution

It introduces a method using surface shape to analyze rotating star models, enabling separation of shape and mass effects, and provides insights into temperature distribution independence from mass.

Findings

Surface shape effectively distinguishes rotation effects.

Temperature ratios are nearly independent of stellar mass.

Models cover a wide range of masses and rotation rates.

Abstract

Zero age main sequence models of uniformly rotating stars have been computed for ten masses between 1.625 and 8 M_\odot and 21 rotation rates from zero to nearly critical rotation. The surface shape is used to distinguish rotation rather than the surface equatorial velocity or the rotation rate. Using the surface shape is close to, but not quite equivalent to using the ratio of the rotation rate to the critical rotation rate. Using constant shape as the rotation variable means that it and the mass are separable, something that is not true for either the rotation rate or surface equatorial velocity. Thus a number of properties, including the ratio of the effective temperature anywhere on the surface to the equatorial temperature, are nearly independent of the mass of the model, as long as the rotation rate changes in such a way to keep the surface shape constant.