Conveners
5 Element production and stellar evolution: MP/UMP and Novae
- André Maeder (Geneva Observatory)
John Cowan
(University of Oklahoma)
27/06/2006, 08:30
Element production, stellar evolution and stellar explosions
Invited
Abundance observations indicate the presence of
rapid-neutron capture (i.e., r-process) elements in
old Galactic halo and globular cluster stars. These
observations provide insight into the nature of the earliest
generations of stars in the Galaxy -- the progenitors of the
halo stars -- responsible for neutron-capture synthesis of
the heavy elements.
The large
star-to-star...
Jordi Jose
(Institut d'Estudis Espacials de Catalunya/UPC)
27/06/2006, 09:00
Element production, stellar evolution and stellar explosions
Oral contribution
Classical nova outbursts are powered by thermonuclear runaways (hereafter,
TNRs) that take place in the hydrogen-rich accreted envelopes of white dwarfs in
close binary systems. Extensive numerical simulations of nova outbursts have shown
that the accreted envelopes attain peak temperatures ranging between 100 and 400 MK
for about several hundred seconds, and therefore, their ejecta is...
Georges Meynet
(Geneva Observatory)
27/06/2006, 09:20
Element production, stellar evolution and stellar explosions
Oral contribution
Massive stars with no or very little amount of metals are generally
considered as having very weak stellar winds. We reconsider here
this question through stellar models accounting for the effects of
axial rotation and show that rotating models of massive stars
might lose a significant fraction of their initial mass through mass loss.
The physical mechanisms triggering these mass losses...
Inese Ivans
(Carnegie Observatories & princeton university)
27/06/2006, 09:40
Invited
Numerous signatures of r- and s-process nucleosynthesis can be observed in the
photospheres of stars. To date, however, the stellar abundance determinations of
many of the elements have been scarce because a large portion of the dominant
atomic transitions reside in the UV. To be reported in the context of other recent
results of neutron-capture studies, are the abundances (or upper...
Timothy Beers
(Michigan State University and JINA)
27/06/2006, 10:10
Element production, stellar evolution and stellar explosions
Oral contribution
Recent large surveys of metal-poor stars in the Galaxy have revealed that a
surprising fraction of them are enhanced in their carbon-to-iron ratios by
factors of from 10-10,000 relative to the solar ratio. Although most of the
stars in the metallicity interval -2.7 < [Fe/H] < -2.0 are likely to have arisen
from Asymptotic Giant Branch processing (and subsequent dumping via mass
transfer...
