POSTER PAPER 9.09
Assessment of the Tip-AGB Mass-loss Using Synthetic Stellar Samples in the (MBol , J--K) Diagram
Klaus-Peter Schroeder, Jan Martin Winters
Institute: Astronomy Centre, University of Sussex (UK)
Institute: MPI fuer Radioastronomie, Bonn (GER)
Contact Email: kps@star.cpes.susx.ac.uk
Abstract:
A new approach is presented here to interpret the large amount
of IR survey data in a most direct and quantitative way, by means of
modeling the, e.g., (MBol , J--K) diagram. Combining
stellar evolution with dust-driven wind models, we have produced a
grid of stellar evolution tracks (for solar abundances) with a mass-loss
description for carbon-rich tip-AGB stars derived from the latest
version of the self-consistent, pulsating Berlin wind models. By
random distribution in age and mass, dependent only on the given IMF,
a large synthetic sample of tip-AGB cool giant
stars with very strong mass loss has then been generated, including
relevant IR properties.
The synthetic cool giant sample presented here is modeled on the
solar neighbourhood (d < 50 pc) and its IMF, for 1000x more stars.
It provides a detailed inventory of the individual
stellar mass loss, the stellar masses (present and initial) and ages.
From 5067 giants with B--V > 1.4, only 14 objects are
found in their brief (final 30,000 years) superwind phase
(J--K > 6.5). However, these 14 carbon-rich tip-AGB giants
produce more than 1/2 of the collective mass-loss of the whole stellar
sample. Since these crucial objects
are likely to be under-represented in observed samples, a synthetic sample
is required to account for them without bias.
Index Keywords: Tip-AGB; Mass-loss
Previous: Boeger
Next: Fekel
Up: Poster Index
Up: Top Index
Manuscript submitted: 2001-Aug-24
"The Future of Cool-Star Astrophysics", 2003, Eds. A. Brown,
G. M. Harper, & T. R. Ayres.
Proceedings of 12th Cambridge Workshop on Cool Stars, Stellar Systems,
& The Sun,
© 2003 University of Colorado.