New approach to measure double-differential charged-particle emission cross sections of several materials for a fusion reactor

摘要

Double-differential charged-particle emission cross section (DDXc) is a fundamental value to estimate nuclear heating and material damages in fusion reactor development. In the present study, measurements of DDXc for several light elements have been carried out with a newly developed spectrometer. In the spectrometer, a good signal-to-noise ratio and very low minimum measurable energy were realized by using a pencil-beam DT neutron source of FNS in JAERI and a counter-telescope system with very thin silicon surface barrier detectors of appropriate thicknesses. The detailed DDXc data in a wide emission energy range were obtained for ~(27)Al, ~9Be, ~(nat)C and ~(19)F. For ~(27)Al(n, xα) reactions, the measured total cross section agreed well with the evaluated data. For ~9Be(n,xα) reactions, there were differences in the α-particle emission DDX between measurement and the evaluated data in the detail of energy structure. For ~(nat)C(n,xα) reaction, a large discrepancy between the present result and the previous experimental data appeared. For ~(19)F(n, charged-particle) reactions, some peaks corresponding to excited states of the residual nuclei were observed in the energy spectrum of emitted proton, deuteron, and triton particles.