Geo-neutrinos, Mantle Circulation and Silicate Earth

In preparation to the experimental results which will be available in the future, we consider geo-neutrino production in greater detail than in [F. Mantovani et al., arXiv:hep-ph/0309013], putting the basis for a more refined model. We study geo-neutrino production for different models of matter circulation and composition in the mantle. By using global mass balance for the Bulk Silicate Earth, the predicted flux contribution from distant sources in the crust and in the mantle is fixed within +-15% (full range). A detailed geological and geochemical investigation of the region near the detector has to be performed, for reducing the flux uncertainty from fluctuations of the local abundances to the level of the global geochemical error. A five-kton detector operating over four years at a site relatively far from nuclear power plants can measure the geo-neutrino signal with 5% accuracy (1 sigma). It will provide a crucial test of the Bulk Silicate Earth and a direct estimate of the radiogenic contribution to terrestrial heat.