Abundance analysis of benchmark M dwarfs

TL;DR

This study provides detailed chemical abundances of Fe, Ti, and Ca for a small sample of well-characterized M dwarfs, establishing benchmarks for future spectroscopic analyses and contributing to understanding stellar and galactic chemical evolution.

Contribution

It offers a new benchmark set of M dwarf abundances using high-resolution spectroscopy and differential analysis, aiding future large-scale stellar surveys.

Findings

Abundances of Fe, Ti, and Ca mostly agree with literature within uncertainties.

The differential method reduces systematic errors in abundance determination.

Benchmark M dwarf abundances can improve models of galactic chemical evolution.

Abstract

Abundances of M dwarfs, being the most numerous stellar type in the Galaxy, can enhance our understanding of planet formation processes. They can also be used to study the chemical evolution of the Galaxy, where in particular alpha-capture elements play an important role. We aim to obtain abundances for Fe, Ti, and Ca for a small sample of well-known M dwarfs for which interferometric measurements are available. These stars and their abundances are intended to serve as a benchmark for future large-scale spectroscopic studies. We analysed spectra obtained with the GIANO-B spectrograph. Turbospectrum and the wrapper TSFitPy were used with MARCS atmospheric models in order to fit synthetic spectra to the observed spectra. We performed a differential abundance analysis in which we also analysed a solar spectrum with the same method and then subtracted the derived abundances line-by-line. The median was taken as the final abundance for each element and each star. Our abundances of Fe, Ti, and Ca agree mostly within uncertainties when comparing with other values from the literature. However, there are few studies to compare with.