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[en] The nuclear gamma astronomy is presented, in particular the Gamma Ray Observatory, an enormous eight tonnes machine fitted with gamma telescopes, scheduled for launching around 1985. It is thereby hoped to study the natural nuclear reactions which occur when stars explode
[fr]On presente l'astronomie gamma nucleaire, et en particulier le Gamma Ray Observatory, un enorme engin de 8 tonnes equipe de telescopes gamma qui devrait etre lance vers 1985. On espere ainsi etudier les reactions nucleaires naturelles qui se produisent au cours de l'explosion des etoiles
[en] The 17O(p, α)14N reaction is one of the most important ones to be studied in order to get more information about the fate of 17O in different astrophysical scenarios. We report on the indirect measurement of the 17O(p, α)14N reaction at energies below 300 keV by using the Trojan Horse Method. The experimental approach and the preliminary results will be discussed.
[en] While neutron-antineutron oscillations are possible in many nonstandard theories (ΔB=2) with intermediate mass scales M=O(106)GeV the estimated oscillation periods τ=O(107) s vary by many orders of magnitude. I consider the effects of ambient neutrons transforming into antineutrons at cosmological times between 1 s and 106 s age of the universe when the light nuclei are synthesized. The calculations show that there is no influence on the element abundances if τ≥105 s. No constraints on a primordial magnetic field can be derived for so large oscillation periods
[en] Nuclear astrophysics aims to measure nuclear-reaction cross sections of astrophysical interest to be included into models to study stellar evolution and nucleosynthesis. Low energies, < 100 keV, are requested for this is the window where these processes are more effective. Two effects have prevented to achieve a satisfactory knowledge of the relevant nuclear processes, namely the Coulomb barrier exponentially suppressing the cross section and the presence of atomic electrons. These difficulties have triggered theoretical and experimental investigations to extend our knowledge down to astrophysical energies. For instance, indirect techniques such as the Trojan Horse Method and new experimental facilities such as deep underground laboratories have been devised yielding new cutting-edge results.
[en] The number of neutrino types (Nν) allowed by primordial nucleosynthesis (NS) and by supernova 1987A (SN) are discussed. NS just allows 4 types while SN allows 6. Results from CERN announced after the workshop indicate that Nν=3. However, the CERN result does not include supersymmetry particles such as the photino, while the astronomical limit does not include particles of mass >1-10Mev