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arXiv · 0902.0783

Direct measurement of the 15N(p,gamma)16O total cross section at novae energies

D Bemmerer·A Caciolli·R Bonetti·C Broggini·F Confortola·P Corvisiero·H Costantini·Z Elekes·A Formicola·Zs Fulop·G Gervino·A Guglielmetti·C Gustavino·Gy Gyurky·M Junker·B Limata·M Marta·R Menegazzo·P Prati·V Roca·C Rolfs·C Rossi Alvarez·E Somorjai·O Straniero
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Abstract

The 15N(p,gamma)16O reaction controls the passage of nucleosynthetic material from the first to the second carbon-nitrogen-oxygen (CNO) cycle. A direct measurement of the total 15N(p,gamma)16O cross section at energies corresponding to hydrogen burning in novae is presented here. Data have been taken at 90-230 keV center-of-mass energy using a windowless gas target filled with nitrogen of natural isotopic composition and a bismuth germanate summing detector. The cross section is found to be a factor two lower than previously believed.

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D Bemmerer, A Caciolli, R Bonetti, C Broggini, F Confortola, P Corvisiero, H Costantini, Z Elekes, A Formicola, Zs Fulop, G Gervino, A Guglielmetti, C Gustavino, Gy Gyurky, M Junker, B Limata, M Marta, R Menegazzo, P Prati, V Roca, C Rolfs, C Rossi Alvarez, E Somorjai, O Straniero. 2009-02-04. Direct measurement of the 15N(p,gamma)16O total cross section at novae energies. https://doi.org/10.1088/0954-3899%2F36%2F4%2F045202

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