Chemical Tagging Hyades Supercluster as a consistency test of Stellar Kinematic Groups

TL;DR

This study uses chemical tagging and spectroscopic data to identify and confirm members of the Hyades Supercluster, testing the consistency of stellar kinematic groups through chemical homogeneity.

Contribution

It provides a new, detailed chemical tagging approach combined with spectroscopic ages to reliably identify members of the Hyades Supercluster.

Findings

Identified likely members based on chemical homogeneity.

Derived stellar parameters consistent with galactic trends.

Confirmed some stars as members using differential abundances.

Abstract

Stellar Kinematic Groups are kinematical coherent groups of stars which may share a common origin. These groups spread through the Galaxy over time due to tidal effects caused by galactic rotation and disk heating, however the chemical information survives. The aim of chemical tagging is to show that abundances of every element in the analysis must be homogeneous between members. We have studied the case of the Hyades Supercluster in order to compile a reliable list of members (FGK stars) based on chemical tagging information and spectroscopic age determinations of this supercluster. This information has been derived from high-resolution echelle spectra obtained during our surveys of late-type stars. For a small subsample of the Hyades Supercluster, stellar atmospheric parameters (T_eff, log g, xi and [Fe/H]) have been determined using an automatic code which takes into account the sensibility of iron EWs measured in the spectra. We have derived absolute abundances consistent with galactic abundance trends reported in previous studies. The chemical tagging method has been applied with a carefully differential abundance analysis of each candidate member of the Hyades Supercluster, using a well-known member of the Hyades cluster as reference. A preliminary research has allowed us to find out which stars are members based on their differential abundances and spectroscopic ages.