1997/10/06 by Cheryl Frost, Robert Cannon, Frost, Cheryl +7
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9710054
4 pages, 2 figures included. Note that these are quality-reduced figures for net transmission. If you want best quality figures, these are available from http://www.maths.monash.edu.au/~johnl/preprints/preprints.html
arxiv created 1997/10/06 · arxiv updated 2009/12/01
It is currently accepted that Hot-Bottom-Burning (HBB) in intermediate-mass asymptotic giant branch (AGB) stars prevents the formation of C~stars. Nevertheless, we present in this paper the results of some detailed evolutionary calculations which show that even with HBB we obtain C~stars at the highest luminosities reached on the AGB. This is due to mass-loss reducing the envelope mass so that HBB ceases but dredge-up continues. The high mass-loss rate produces an optically thick wind before the star reaches C/O>1. This is consistent with the recent results of van Loon et al. (1997a,b) who find obscured C~stars in the Magellanic Clouds at luminosities up to Mbol = -6.8.