| 摘要 |
PURPOSE:To measure the energy of neutron while satisfying the four conditions of a neutron detector by taking the coincidence of the output by the incident neutron of a plastic scintillator having the thickness below the range of recoil proton and the output from an energy measuring device by the recoil proton past a porous collimator. CONSTITUTION:The collimated neutron flux is made incident on the plastic scintillator 3 having the thickness below the range of the recoil proton and the fluorescence by the recoil proton is detected by a photomultiplier 4b. The gamma-rays made incident simultaneously on said scintillator transmit mostly the scintillator 3 with substantially no energy loss and the fluorescence thereof is negligible. The recoil proton emitted to a scattering angle 0 is made incident on a gas scintillator 10 through the porous collimator 9a and the fluorescence thereof is detected by a photomultiplier 4c. The outputs from the multipliers 4b, 4c are passed through preamplifiers 6b, 6c and gate pulse generating circuits 11a, 12a and the coincidence thereof is taken in a gate circuit 12a, the output from which is fed via a pulse height analyzer 5b or pulse height discriminator 13 to an integrator 14. |
