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EXOTIC NUCLEI AND NUCLEAR∕PARTICLE ASTROPHYSICS (III): From Nuclei to Stars, Sinaia : Roumanie (2010)
First Experimental Measurement of the 18O(p,α)15N Reaction at Astrophysical Energies
M. La Cognata, M. L. Sergi, C. Spitaleri, A. Mukhamedzhanov, A. Coc1, S. Cherubini, V. Goldberg, M. Gulino, F. Hammache2, B. Irgaziev, G. Kiss, L. Lamia, R. G. Pizzone, S. Romano, N. De Sereville2, R. Tribble, A. Tumino
(11/2010)

The 18O(p,α)15N and 17O(p,α)14N reactions are of primary importance in several as-trophysical scenarios, including nucleosynthesis inside Asymptotic Giant Branch stars and oxygen and nitrogen isotopic ratios in meteorite grains. They are also key reactions to understand exotic systems such as R-Coronae Borealis stars and novae. Thus, the measurement of their cross sections in the low energy region can be crucial to reduce the nuclear uncertainty on theoretical predictions, because the resonance parameters are poorly determined. The Trojan Horse Method, in its newly developed form particularly suited to investigate low-energy resonances, has been applied to the 2H(18O,α15N)n and 2H(17O,α14N)n reactions to deduce the 18O(p,α)15N and 17O(p,α)14N cross sections at low energies. Resonances in the 18O(p,α)15N and 17O(p,α)14N excitation functions have been studied and the resonance parameters deduced.
1 :  CSNSM - Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse
2 :  IPNO - Institut de Physique Nucléaire d'Orsay
Physique/Astrophysique/Astrophysique stellaire et solaire

Planète et Univers/Astrophysique/Astrophysique stellaire et solaire

Physique/Physique Nucléaire Expérimentale
nucleosynthesis – resonance – white dwarfs – isotope effects – Cosmic ray nucleosynthesis – Resonance reactions – Faint blue stars – degenerate stars – nuclei of planetary nebulae – Hyperfine interactions and isotope effects – Jahn-Teller effect