The reaction 12C~-12C has been studied in the energy range Ecru=2.45-6.15 MeV by 7ray spectroscopy. Gamma-ray transitions from a large number of excited states in 2~ 23Na and 23Mg were observed, which show strong and rapid yield variations. When the influence of the Coulomb barrier is removed, these structures appear superimposed on a flat reaction yield, which does not show a strong increase at low energies, in contrast to previous work. These results obviate the need for the hypothesis of absorption under the barrier at least down to E~m=2.45 MeV. The nuclear and astrophysical aspects of the data are discussed. E Nuclear Reactions: ~2C+12C, MeV, measured as(E), Iv(O ). Deduced astrophysical S-factor. Solid state targets with low hydrogen contamination. Ge(Li) detector.

The ~SN(p, %)lzC reaction has been investigated in the energy range of Ep(lab)=78-810keV. The measurement of the excitation functions and s-particle angular distributions involved solid targets as well as a quasi-point supersonic jet gas target. The determination of absolute cross sections has been carried out with the gas target. The observed energy dependence of the total cross sections can be described in terms of two-level Breit-Wigner shapes including the resonances at Ep(J~)=335(1 -) and 1,028(1-) keV. The data lead to a zero-energy intercept of the astrophysical S(E) factor of S(0)=65_+4 MeV-b. The angular distributions are asymmetric around 90 ~ and require an additional amplitude in the reaction mechanism, which interferes predominantly with the 335 keV resonance. The origin of this background amplitude is discussed. ENuclear Reaction: 15N(p, c%)~2C, Ev(lab)=78-810keV; measured c~(E, 0). Deduced astrophysical S-factor. Enriched 15N solid target and supersonic jet gas target,

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