An LTE effective temperature scale for red supergiants in the Magellanic clouds

TL;DR

This study derives a consistent effective temperature scale for red supergiants in the Magellanic Clouds using LTE models, revealing a universal temperature scale across different metallicity environments.

Contribution

It provides the first self-consistent LTE-based Teff scale for red supergiants in the Magellanic Clouds, validated through extensive testing and Monte Carlo simulations.

Findings

A unified Teff scale independent of metallicity environment.

Robust stellar parameters with quantified uncertainties.

Validation of LTE models for cool supergiants in different environments.

Abstract

We present a self-consistent study of cool supergiants (CSGs) belonging to the Magellanic clouds. We calculated stellar atmospheric parameters using LTE KURUCZ and MARCS atmospheric models for more than 400 individual targets by fitting a careful selection of weak metallic lines. We explore the existence of a T eff scale and its implications in two different metallicity environments (each Magellanic cloud). Critical and in-depth tests have been performed to assess the reliability of our stellar parameters (i.e. internal error budget, NLTE systematics). In addition, several Montercarlo tests have been carried out to infer the significance of the Teff scale found. Our findingspoint towards a unique Teff scale that seems to be independent of the environment.