Uncertainties and systematics in stellar evolution models of Red Giant Stars

TL;DR

This paper reviews the current uncertainties in low-mass stellar evolution models during the Red Giant Branch stage, emphasizing the impact of physical process uncertainties on model accuracy and comparison with observations.

Contribution

It provides a comprehensive review of the main uncertainties affecting low-mass stellar models during the Red Giant phase.

Findings

Uncertainties in mixing process efficiencies significantly affect model predictions.

Physical process uncertainties impact the interpretation of observational data.

Review highlights areas needing further research to improve model reliability.

Abstract

In this last decade, our knowledge of evolutionary and structural properties of stars of different mass and chemical composition has significantly improved. This notwithstanding, updated stellar models are still affected by significant and, usually, not negligible uncertainties. These uncertainties are related to our poor knowledge of some physical processes occurring in the real stars such as the efficiency of mixing processes. These drawbacks of stellar models have to be properly taken into account when comparing theory with observations. In this paper we briefly review current uncertainties affecting low-mass stellar models, i.e. those structures with mass in the range between 0.6 Msun and ~1.4 Msun, during the Red Giant Branch stage.