Neutron Diagnostic Instrumentations for the Fuze Device

Abstract

Fusion reactor concepts need to demonstrate the ability to produce controlled nuclear fusion. Spectroscopy of neutrons can demonstrate how well the device controls the reaction, whereas the yield shows the efficacy of the device. Both detection systems are diagnostics for D-D neutrons on Zap Energy’s FuZE Shear-Flow-Stabilized Z-Pinch device. Currently two types of activation detectors are used to corroborate the neutron yield. A total of 22 fast plastic scintillating detectors give energy and timing information; 3 additional scintillators are capable of performing pulse shape discrimination to seperate neutrons from bremsstrahlung x-rays. For activation detectors, one is arsenic with an appreciable capture cross section and emitting 0.3 MeV photons with a half life of 17 ms. The other is a LaBr3 activation detector capped with yttrium. This detector features time-resolved multichannel analysis of pulse height spectra coming from two different activations of yttrium and bromide which release photons of 909keV and 208keV, respectively. Fast plastic scintillators give timing information on incoming radiation, and spectroscopic information from the recoil protons. The pulse shape discriminating scintillator can further more identify shots that produce hard X-rays. The combination of these diagnostics allows for both recoil proton spectroscopy and yield measurements.