Abstract:
Plates of boron carbide B$_{4}$C were used as refractory targets for determination of energy and fluencies of protons collectively accelerated in a Luce diode accelerator by control of $^{7}$Be and $^{13}$N gamma-radioactivities induced by nuclear reactions $^{10}$B$(p,\alpha)^{7}$Be and $^{12}$C$(p,\gamma)^{13}$N, respectively. The Luce diode exploited a cylindrical tungsten rod as a cathode and polyethylene washer as an anode, producing pulsed electron beams with durations and currents of up to 100 ns and 30 kA at voltages of 250 kV. The technique allows controlling proton energies within the range of 500–1500 keV and fluencies of up to 5 $\times$ 10$^{13}$ protons per cm$^2$ per pulse.