Dead-time measurement of neutron counters by reactor-power variational technique

The measurements of dead time of BF₃, ³He, fission and proton-recoil neutron counters were performed on the basis of the reactor-power variational technique in the reactor, UTR-KINKI reactor. The advantage of this method consists in making it possible to change the flux of irradiation field continuously and over a wide range. The reactor UTR-KINKI is well suited for the measurements since the power of the reactor can be easily changed and the range of flux is just appropriate to evaluate the dead time. The results indicate that the nonparalysable model for the dead time characteristics is applicable to the counters employed. The measured dead time of fission counter is about 1.4 μs, while those of others range of 6-9 μs. (author)