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Origin of the elements Which reactions Which physical conditions Which astrophysical sites Which quantities Yields depend on reaction rates , M , Z, treatment of convection, Mass loss , V rot , B magn , Interactions in close binaries , Explosion mechanism - PowerPoint PPT Presentation
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Origin of the elements
Which reactions Which physical conditions Which astrophysical sites Which quantities
Yields depend onreaction rates,
M, Z,
treatment of convection,Mass loss,
Vrot, Bmagn,
Interactions in close binaries, Explosion mechanism
Explosive nucleosynthesis
1D-3D models
Nomoto et al. 2013 (ARAA)
Evolution of stellar systems
Part of history hidden in the abundances of the elements.
How to constrain the yields?
INDVIDUAL STARS
Check of in situ processes (WR) Composition of the ejecta of Supernovae Asteroseismology Unaltered surface composition of stars composed from ISM enriched by one or two nucleosynthetic events or a restricted mass range of stars like EMP halo stars, CEMP stars General properties of stars
COLLECTIVE EFFECTS
ISM abundances (in primordial galaxies)
Nomoto et al. 2013 (ARAA)
STRIKING OBSERVATIONAL FACTS (EMP STARS)
1) Scatter: different according to the elements considered
Cayrel et al. 2004
2) No sign of Pair Instability Supernovae
3) Important amount of primary nitrogen
4) More carbon, less oxygen produced at low Z ?
5) CEMP, CRUMP (no, r, s, r and s)
6) The O-Na, Mg-Al anticorrelation in globular cluster stars
7) Helium-rich stars in globular clusters
Israelian et al. 2004, Centurion et al 2003
Spite et al 2005 Norris et al 1997
Mc William et al 95; Barbuy et al. 96; Christlieb et al. 04; Frebel et al. 05; Plez & Cohen 05
Gratton et al 2004; Piotto et al 2005
Observations:
IN THE FIELD IN GLOBULAR CLUSTERS
IN THE HALO TWO KINDS OF CHEMICALLY PECULIAR STARS
STARS MADE OF
H- and He-burning productsH-burning products
Norris et al 97Gratton et al. 2004
Large scatter
SAME MASS: 60 Msol, SAME Vini=800 km s-1
Z=0.00050 Z=0.00001
Slow wind: MSOnly enriched in
H-burningproducts
Slow wind: YSGenriched in
H- and He-burningproducts
WW95
CL04
Netal06
V=0, Hetal05
V=300, Hetal05