Dr Jean-Christophe David (CEA)
Spallation reactions play a role in the production of stable and radioactive isotopes in meteorites by galactic cosmic ray (GCR) particles. For several decades cosmogenic nuclide production rates have been measured in different types of meteorites and calculation models have been improved. The main microscopic ingredients of these models are: i) the particle fluxes responsible of the nuclide production (primary and secondary particles) and ii) the production cross-section of nuclides from a given particle (in the whole energy range). Up to now the best choice seems to compute the particle fluxes with Monte-Carlo codes (ex: LAHET code system - LCS) and use experimental measurement for the production cross section, if available. Meanwhile spallation models have also been improved the last ten years, and especially the combination INCL4-Abla. INCL4 (Intra-Nuclear Cascade Liège) is the intra-nuclear part and Abla deals with the deexcitation phase. These two models have been recently benchmarked with about ten other models within the "Benchmark of spallation models" carried out by IAEA and it comes out that INCL4-Abla is one of the best combinations to describe spallation reactions. Then we will show, with microscopic excitation functions, the great improvement done in the estimates of nuclides of interest in stony and iron meteorites (3He, 10Be, 21Ne, 26Al, 36Cl, ...). Moreover INCL4-Abla can emit nucleons, d, t, 3He, α and heavy ions, and computes reactions with nucleons, d, t, 3He and α as projectiles. Then we can study p+Fe, n+Fe and α+Fe as well where experimental excitation functions exist. It has to be mentioned that these new versions of INCL4 and Abla have been implemented in a transport code, MCNPX, and thus macroscopic calculations with inter-nuclear cascades can be done.