Characterization of specific nuclear reaction channels by deconvolution in the energy space of the total nuclear cross-section of protons - applications to proton therapy and technical problems (transmutations)

Abstract

The total nuclear cross-section Q tot (E) resulting from the interaction of protons with nuclei is decomposed in 3 different contributions: (1) elastic scatter at the complete nucleus, which adopts a part of the proton kinetic energy; (2) inelastic scatter at a nucleus, which changes its quantum numbers by vibrations, rotations, transitions to excited states; 3. proper nuclear reactions with change of the mass and/or charge number. Then different particles leave the hit nucleus (neutrons, protons, etc.), which is now referred to as 'heavy recoil' nucleus. The scatter parts of Q tot (E) according to points 1 and 2 can be removed by a deconvolution acting at Q tot (E) in the energy space. The typical nuclear reaction channels are mainly characterized by resonances of a reduced cross-section function Q red (E). The procedure is applied to cross-sections of therapeutic protons and also to Cs 55 137 as an example with technical relevance (transmutations with the goal to drastically reduce its half-time.