Rechercher des projets européens

Nuclear reaction studies relevant to the astrophysical p-process nucleosynthesis (ATOMKI-PPROCESS)
Date du début: 1 juil. 2008, Date de fin: 30 juin 2013 PROJET  TERMINÉ 

The astrophysical p-process, the stellar production mechanism of the heavy, proton rich isotopes (p-isotopes), is one of the least studied processes in nucleosynthesis. The astrophysical site(s) for the p-process could not yet be clearly identified. In order to reproduce the natural abundances of the p-isotopes, the p-process models must take into account a huge nuclear reaction network. A precise knowledge of the rate of the nuclear reactions in this network is essential for a reliable abundance calculation and for a clear assignment of the astrophysical site(s). For lack of experimental data the nuclear physics inputs for the reaction networks are based on statistical model calculations. These calculations are largely untested in the mass and energy range relevant to the p-process and the uncertainties in the reaction rate values result in a correspondingly uncertain prediction of the p-isotope abundances. Therefore, experiments aiming at the determination of reaction rates for the p-process are of great importance. In this project nuclear reaction cross section measurements will be carried out in the mass and energy range of p-process to check the reliability of the statistical model calculations and to put the p-process models on a more reliable base. The accelerators of the Institute of Nuclear Research in Debrecen, Hungary provide the necessary basis for such studies. The p-process model calculations are especially sensitive to the rates of reactions involving alpha particles and heavy nuclei. Because of technical difficulties, so far there are practically no experimental data available on such reactions and the uncertainty in these reaction rates is presently one of the biggest contributions to the uncertainty of p-isotope abundance calculations. With the help of the ERC grant the alpha-induced reaction cross sections can be measured on heavy isotopes for the first time, which could contribute to a better understanding of the astrophysical p-process.

Details

Projet Website