Characterization of first prototypes of thin targets for the NUMEN Experiment

The NUMEN Experiment, at INFN-LNS, aims to get information on the nuclear matrix elements of the neutrinoless double beta decay, by measuring double charge exchange reactions cross-sections. To get a good energy resolution, target thickness must be minimized. To allow heat dissipation (intense beams will be used), around 400nm of target isotope will be deposited on a 2 μm thick highly oriented pyrolytic graphite substrate, that has high in-plane thermal conductivity. First NUMEN target prototypes of tin and tellurium have been produced. Thickness and uniformity analysis performed by alpha-particle transmission and Rutherford backscattering spectroscopy will be reported, together with the evaluation of the energy resolution with a Monte Carlo code.