Preparation & Scientific Explotation of CARMENES: The Metallicity of M-dwarfs

TL;DR

This paper details the process of compiling and analyzing data from various catalogues to calibrate metallicity in M-dwarfs within binary systems, supporting the CARMENES exoplanet survey.

Contribution

It introduces new spectroscopic and photometric metallicity calibrations for M-dwarfs using binary systems, validated through proper motion analysis and catalog data.

Findings

Two types of metallicity calibrations obtained

Physical pairs confirmed via proper motion analysis

Data compilation from multiple catalogues

Abstract

CARMENES is a next-generation instrument being built by a consortium of German and Spanish institutions to carry out a survey of 300 M-type dwarf stars with the goal of detecting exoearths by radial-velocity measurements. To collect relevant information from different on-line catalogues for a given sample of 209 binary or multiple star systems, formed by F, G or K primary star and an M-dwarf (or late-K) companion. To prove if the pair is indeed a physical pair, to obtain different metallicity calibrations in K-band with these binary systems. The data compilation from every star has been done searching in catalogues in VizieR and the literature. In addition, physical pair checking has been done studying the collected proper motions from both stars (primary and secondary) and using two tools from the Virtual Observatory: Aladin and TopCat. From a list of suitable systems, two different types of calibrations had been obtained: spectroscopic and photometric. In order to determine these calibrations, we have considered that metallicity from the primary star, determined by the CARMENES UCM research group, is equal to the secondary star.