Period - Mass-loss Rate Relation of Miras with and without Tc

Author(s)
Stefan Uttenthaler
Abstract

We present the discovery that Mira variables fall into two distinct sequences in a plot of near- to mid-IR color versus pulsation period diagram, if a distinction is made with respect to the presence of technetium (Tc) in the stars. Tc is an indicator of recent or ongoing deep mixing during a third dredge-up event. At a given period, the Tc-poor Miras are redder in K-[22] (i.e. have a higher dust mass-loss rate) than the Tc-rich Miras. This is counter-intuitive since the Tc-rich Miras are expected to be more evolved and should have a higher mass-loss rate. In this contribution we give an update on this recently discovered conundrum.

Organisation(s)
Department of Astrophysics
Pages
49 - 56
Publication date
08-2015
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Portal url
https://ucrisportal.univie.ac.at/en/publications/period--massloss-rate-relation-of-miras-with-and-without-tc(23537a8c-a93c-4d98-ab9b-39a71b05beae).html