Origin of the elements Which reactions Which physical conditions Which astrophysical sites

1. Origin of the elements • Whichreactions • Whichphysical conditions • Whichastrophysical sites • Whichquantities • Yieldsdepend on • reactionrates, • M, • Z, • treatmentof convection, • Mass loss, • Vrot, • Bmagn, • Interactions in close binaries, • Explosion mechanism • Explosive nucleosynthesis • 1D-3D models Evolution of stellarsystems Part of historyhiddenin the abundances of the elements. Nomoto et al. 2013 (ARAA)

2. 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 • composedfromISMenriched by one or • twonucleosyntheticevents 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)

3. STRIKING OBSERVATIONAL FACTS (EMP STARS) 1) Scatter: different according to the elements considered 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 Observations: Cayrel et al. 2004 Spite et al 2005 Israelian et al. 2004, Centurion et al 2003 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

4. IN THE HALO TWO KINDS OF CHEMICALLY PECULIAR STARS IN THE FIELD IN GLOBULAR CLUSTERS Gratton et al. 2004 Norris et al 97 Large scatter STARS MADE OF H-burningproducts H- and He-burningproducts

5. SAME MASS: 60 Msol, SAME Vini=800 km s-1 Z=0.00001 Z=0.00050 Slow wind: YSG enriched in H- and He-burning products Slow wind: MS Onlyenriched in H-burning products

9. Netal06 V=0, Hetal05 V=300, Hetal05 WW95 CL04