A ray-trace type counter telescope for neutron spectrometry

A compact recoil proton counter telescope with two position sensitive proportional counters (PSPCs) for neutron spectrometry has been developed. This counter telescope consists of a radiator (a thin polyethylene film), two PSPCs used as /spl Delta/E detector and a Si-SSD used as E detector. Using the position information extracted from two PSPCs, the three-dimensional trajectory of the recoil proton and the recoil angle can be determined event by event. The performance of this counter telescope was tested by the measurement of 7.2 MeV neutrons produced from D-D reactions, and it was shown that the energy spectra of neutrons could be obtained by determining the energy of each incident neutron using a recoil angle.