A study on natural background neutron dose

In order to monitor the neutron dose in the environment of the Synchrotron Radiation Research Center, the sensitivity of the monitor system to the natural background cosmic-ray neutrons must be established. Large-size BF/sub 3/ counters with and without an 8.5-cm polyethylene enclosure were used to measure the cosmic-ray neutrons in the Nuclear Engineering Building, NTHU. The response functions of the BF/sub 3/ counters were calculated by using ANISN code performed in adjoint mode. By applying the cosmic-ray neutron spectrum and the detector response functions the measured counting rates of the BF/sub 3/ counters were converted to deliver the annual dose of cosmic-ray neutrons. The shielding effect of the concrete slabs and windows of the building was determined by the measured data and compared to that predicted by neutron transport calculations.<
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