Stellar Nucleosynthesis

x about a sequence of reVlew lectures, each followed by contributed talks and discussions. The opening session was devoted to reviewing the most recent results concerning the determination of chemical abundances in particularly inte resting objects providing direct evidence for stellar nucleosynthesis (like planetary nebulae, supernovae and supernova remnants). In Session 2 recent results on some relevant nuclear reaction rates have been presented. Session 3 grouped the contributions concerning the quasi-static evolution of normal stars, its relevance for the nucleosynthesis of the varlOUS elements and isotopes, and the comparison of the evolutionary models with the observations. Session 4 addressed the important questions of identifying the precursors of both Type I and Type II supernovae, and of determining the detailed composition of the ejecta by explosive nucleosynthesis associated with these events. Finally, Session 5 was devoted to a presentation of recent calculations of the evolution of hypothetical pre-galactic very massive objects (in cluding their potential role in pre-galactic nucleosynthesis), and to reviewing the progress that has been made in understanding the chemical evolution of galaxies. The discussion during and after talks was spirited and contributed signi ficantly to the succes of the workshop. We regrett for not having been able of reporting it "in toto" in the proceedings. Nevertheless, we hope that what has been recorded may still give to the reader at least part of the excitement we have experienced during the ten days of the workshop.

Proceedings of the Third Workshop of the Advanced School of Astronomy of the Ettore Majorana Centre for Scientific Culture, Erice, Italy, May 11-21, 1983

Inhalt
Session I: Plawetary Nebulae, Supernovae, Supernova Remnants and Cosmic Rays.- Nucleosynthesis and Planetary Nebulae.- Cn 1-1 (= HD 330036): Planetary Nebula or Symbiotic Star?.- Extragalactic Supernovae.- Abundances in Supernova Remnants.- The Nickel and Iron Abundances in the Crab Nebula Filaments.- A Statistical Comparison of Galactic SNRs and Galactic Giant HII Regions.- Wolf-Rayet Stars, Cosmic Rays and Gamma Rays.- Session II: Topics on Nuclear Reactions.- The Ne-Na Cycle and the 12C+? Reaction.- Nuclear Effective Forces and Their Use in Astrophysical Problems.- Session III: Quasi-Static Stellar Evolution and Relatev Nucleosynthesis.- Some Aspects of the Nucleosynthesis in Intermediate Mass Stars.- Hydrostatic Evolution and Nucleosynthesis in Massive Stars.- Nucleosynthesis During the Quasi-Static Evolution of Massive Stars.- Presupernova Yields and Their Dependence on the 12C (?,?) 16O Reaction.- r-Process Production in Low Mass Stars.- Synthetic H-R Diagrams as an Observational Test of Stellar Evolution Theory.- Evidence for a Large Main Sequence Widening: A Plea for Overshooting and Higher Heavy Element Opacity.- On the Structure of the Upper HRD of Humphreys.- Session IV: Supernova Precursors and Explosive Nucleosynthesis.- An Essay on Possible Precursors of Type I Supernovae.- Nucleosynthesis in Type I Supernovae: Carbon Deflagration and Helium Detonation Models.- Type II Supernovae from 810 M? Progenitors.- The Energetics of Type II Supernovae.- Nucleosynthesis in Stellar Explosions.- Session V: Pregalactic Nucleosynthesis and Chemical Evolution of Galaxies.- Massive Objects and the First Stars.- Stellar He Production in a Cold Universe?.- Chemical Abundances and Galaxy Evolution.- Three Problems in the Chemical Evolution of Galaxies.- Problems in the Chemical Evolution of Galaxies.- The Chemical Evolution of Spiral Galaxies: The Galaxy, M31, M33, M83, and M101.- Actinide R-Process Chronometers and ?-Delayed Fission.- Subject (Element) Iwek.