Calculations of total fusion power and spatial distribution of emissivity for a D-T thermal plasma

The preliminary project of a diagnostic tool to measure the neutron emissivity profile for NET (Next European Torus) with an array of collimators is presented. With the help of a neutron transport code the maximum possible number of collimators, compatible with the crosstalk noise and the space available in the NET 2.2.B is determined within these constraints. An array of 17 collimators can be used, and some experimental results are simulated using a Monte Carlo code. These results are analyzed and an inversion procedure is used to obtain the emissivity profile and evaluate the total fusion power. The results show that the total fusion power can be measured within 10% for different emission profiles