The Cassiopeia A progenitor - A consistent evolutionary picture involving supergiant mass loss

Abstract

The observed abundances in the Cas A supernova remnant are used together with results of evolutionary calculations of massive stars to construct an evolutionary picture for the CAS A progenitor star. A consistent picture is presented which involves two periods of mass loss, one while the star was an early-type supergiant, the other in a later evolutionary phase.A review of current observational evidence for mass loss from early-type supergiants and the proposed evolutionary picture for the CAS A progenitor suggest that some massive stars lose over half of their hydrogen envelopes prior to crossing the Hertzsprung gap.