ARES+MOOG - a practical overview of an EW method to derive stellar parameters

TL;DR

This paper provides a comprehensive practical overview of the Equivalent Width (EW) method for deriving stellar parameters, detailing each step with a focus on the ARES+MOOG implementation and including a tutorial for users.

Contribution

It offers a detailed, step-by-step guide to the EW method with practical exercises, emphasizing the ARES+MOOG approach and its specific procedures.

Findings

Clear procedure to determine final stellar parameters

Illustration of dependence of abundances on stellar parameters

Practical tutorial with simple exercises

Abstract

The goal of this document is to describe the important practical aspects in the use of an Equivalent Width (EW) method for the derivation of spectroscopic stellar parameters. A general description of the fundamental steps composing any EW method is given, together with possible differences that may be found in different methods used in the literature. Then ARES+MOOG is then used as an example where each step of the method is described in detail. A special focus is given for the specific steps of this method, namely the use of a differential analysis to define the atomic data for the adopted line list, the automatic EW determinations, and the way to find the best parameters at the end of the procedure. Finally, a practical tutorial is given, where we focus on simple exercises useful to illustrate and explain the dependence of the abundances with the assumed stellar parameters. The interdependences are described and a clear procedure is given to find the "final" stellar parameters.