High Resolution Spectroscopy of the Semi-Regular Variable LR Sco

Abstract

A detailed spectroscopic investigation of LR Sco which was earlier misclassified as R CrB star is made. Atmospheric parameters and elemental abundances are determined using detailed depth-dependent model atmospheres and line synthesis technique. Most of the elements show near solar abundances. The strength of circumstellar components seen in Na D lines are used to derive the mass loss rate. Another independent estimate of mass loss rate is made using the observed infrared flux from 1–100μm. These two approaches lead to nearly the same value of mass loss rate when Mv is assumed to be – 4.5 for this star.