Colliding plasma neutron production at Trident

Trident is a two-beam Nd:glass laser producing typically 100 J at 2ω in 2 ns pulses. Diffraction unlimited f/6 optics reduce the 20-cm-diam beams down to 100 μm diameter. The laser is capable of producing neutrons from D-D and D-T plasmas, and has demonstrated yields of >106 D-D neutrons from colliding plasma geometries. We have combined a previously existing neutron activation technique with two large photomultiplier tubes (PMTs) coupled to scintillators to produce a neutron measuring capability on Trident. In addition, we have coupled a time-of-flight compensated scintillator to a fast microchannel plate PMT to provide neutron energy resolution and hence the potential to measure ion temperatures through time-of-flight spread. The activation technique is sensitive to >105 neutrons per count in its present configuration. The PMT/scintillators have comparable sensitivities. The MCP/PMT/scintillator combination has 220 ps rise time with an order of magnitude less sensitivity. We will describe these detectors and the methods used to calibrate the individual detector sensitivities.