| 摘要 |
This invention relates to a method and apparatus for improving the precision of at least one of neutron coincidence counting and neutron multiplicity counting. The method includes the steps of: (1) sampling the real and accidental coincident pulses at the incoming pulse rate; and (b) sampling the accidental coincidences at a clock rate, wherein the clock rate is much faster than the pulse rate. The clock rate is faster than the pulse rate by a factor of 5 to 10 (in the preferred embodiment, approximately 4 MHz). The apparatus for improving the precision of neutron coincidence counting includes: (a) a shift register; (b) an up-down counter coupled to the shift register; (c) an R+A accumulator coupled to the up-down counter; (d) an A accumulator coupled to the up-down counter; (e) a strobe, the strobe coupled to the R+A accumulator but not to the A accumulator; (f) a clock, the clock coupled to the A accumulator but not to the R+A accumulator, the clock having a rate which is much faster than the pulse rate; and (g) apparatus for reconciling the independent counting of the A accumulator with that of the R+A accumulator. For improving the precision of multiplicity counting the apparatus includes an R+A multiplicity accumulator and an A multiplicity accumulator, The R+A multiplicity accumulator is connected to the up-down counter and the strobe, but not to the clock. The A multiplicity accumulator is coupled to the up-down counter and the clock, but not to the strobe. The clock rate is faster than the pulse rate by a factor of 5-10 (in the preferred embodiment, approximately, 4 MHz). The apparatus also includes apparatus for accumulating the total number of pulses, which is coupled to the strobe and the reconciling apparatus.
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