Conveners
6 Evidence of nucleosynthesis in stars and presolar grains
- Roberto Gallino (Universita' di Torino/INFN Torino)
Andrew Davis
(University of Chicago)
27/06/2006, 11:30
Evidences of nucleosynthesis in stars and in presolar grains
Invited
Presolar SiC grains come from a variety of kinds of stars, but the most common type, the mainstream grains, are
believed to have formed in the outflows of low mass, carbon-rich asymptotic giant branch (AGB) stars.
Measurements of the isotopic composition of the s-process elements Sr, Zr, Mo, Ru and Ba in individual
mainstream SiC grains allow constraints of the range of conditions used...
Ernst Zinner
(Washington University)
27/06/2006, 12:00
Evidences of nucleosynthesis in stars and in presolar grains
Oral contribution
Primitive meteorites contain graphite spherules whose anomalous isotopic compositions indicate a stellar
origin [1]. Because the isolation of presolar graphite grains is difficult, they have been less well studied than
presolar SiC and presolar oxide grains. It has been known that the isotopic compositions of presolar graphite
grains depends on their density, but detailed isotopic...
Maria Lugaro
(University of Utrecht)
27/06/2006, 12:20
Evidences of nucleosynthesis in stars and in presolar grains
Oral contribution
Presolar spinel (MgAl2O4) grains have been recently discovered in meteorites and
represent the most abundant type of presolar oxides. The O, Mg and Al isotopic
compositions of the vast majority of presolar oxide grains indicate that these grains
originated in red giant and asymptotic giant branch (AGB) stars of masses lower than
approximately 3 solar masses. Grain OC2 has a unique...
Roberto Gallino
(University of Torino)
27/06/2006, 12:40
Evidences of nucleosynthesis in stars and in presolar grains
Poster contribution
In AGB stars of low mass and very low metallicity, [Fe/H]<-2, a large abundance of
C12 is mixed with the envelope by each third dredge up episode. The further
activation of the H burning shell at the bottom of the envelope converts almost all
CNO nuclei into N14. Thus the H-burning ashes contain N14 from the original CNO
nuclei, plus an increasing amount of primary N14.
During the...
Gunther Korschinek
(Fachbereich Physik, Technische Universität München)
27/06/2006, 13:00
Experiments in nuclear astrophysics
Invited
Accelerator Mass Spectrometry (AMS) is an extremely sensitive method for
determination of rare ions. Besides ongoing applications in quite different
scientific fields it is still a rather new tool in nuclear astrophysics.
In this presentation I will show the reasons for this unique sensitivity and where
are the limits: from the table top machine too a large facility.
Applications in...
