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Physical Review Letters 95 (2005) 031101 (4 pages)
Hydrogen Burning of $^{17}$O in Classical Novae
A. Chafa, V. Tatischeff1, P. Aguer2, S. Barhoumi, A. Coc1, F. Garrido1, M. Hernanz, J. Jose, J. Kiener1, A. Lefebvre-Schuhl1, S. Ouichaoui, N. De Sereville1, J. -P. Thibaud1
(2005)

We report on the observation of a previously unknown resonance at E=194.1+/-0.6 keV (lab) in the 17-O(p,alpha)14-N reaction, with a measured resonance strength omega_gamma(p,alpha)=1.6+/-0.2 meV. We studied in the same experiment the 17-O(p,gamma)18-F reaction by an activation method and the resonance-strength ratio was found to be omega_gamma(p,alpha)/omega_gamma(p,gamma)=470+/-50. The corresponding excitation energy in the 18-F compound nucleus was determined to be 5789.8+/-0.3 keV by gamma-ray measurements using the 14-N(alpha,gamma)18-F reaction. These new resonance properties have important consequences for 17-O nucleosynthesis and gamma-ray astronomy of classical novae.
1 :  CSNSM - Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse
2 :  CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
Physique/Astrophysique/Cosmologie et astrophysique extra-galactique

Physique/Physique Nucléaire Expérimentale

Planète et Univers/Astrophysique
proton-nucleus reactions – proton radiative capture – alpha particle-nucleus reactions – novae – nuclear energy level transitions – nucleosynthesis
Lien vers le texte intégral : 
http://fr.arXiv.org/abs/astro-ph/0506500