Response functions of an X-rays detecting system for spectral analysis of therapeutic beams

We plan to analyze the bremsstrahlung spectra produced by therapeutic accelerators by an indirect method based on Compton scattering on little target. As a first step, a detailed study of the response functions of a shielded Ge(Li) detector, utilizing Monte Carlo calculations, has been performed for incident energies from 0.1 to 1 MeV. An adequate deconvolution technique has been developed to analyze continuous or discrete non monochromatic spectra. To determine all the response functions, that one needs to know for this procedure, a suitable interpolation of the calculated response functions has been carried out. The results obtained with a 226-Ra source are shown and discussed. Improvement has been reached using a set of experimentally determined response functions obtained by means of monochromatic sources produced with Cyclotron and Reactor