The application of in situ cosmogenic nuclide method in earth sciences is based on the continuous production of nuclides in exposed surfaces. The production rates of nuclides depend on many parameters. Reliable interpretation of the measured in-situ-produced cosmogenic nuclides requires a good understanding of involved nuclear processes. We present results obtained by a pure physical model for the simulation of the relevant processes. This model is enabling an investigation of nuclide production dependence on composition, altitude, geomagnetic field intensity and depth under the surface. LCS and GEANT codes are used in our simulations for the calculation of spectra of particles inducing reactions that produce cosmogenic nuclides. Having calculated neutron fluxes with these codes, the production rates of nuclides are determined by integrating over energy the product of these fluxes with experimental and evaluated cross sections for the reaction producing particular nuclide. Using these codes, theoretical dependencies of production rates at altitude and chemical composition of irradiated object were obtained. We present also new elemental production rates calculated from our new particle fluxes and updated excitation functions, muon fluxes in the atmosphere and on the earth surface. The obtained theoretical values are compared with experimental data and older theoretical estimates.
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See more of The 10th International Conference on Accelerator Mass Spectrometry (September 5-10, 2005)