Measurement and Calculation the Parameters Of The Irradiation Field ForThe Fast Neutron Device in Xi’an Pulse Reactor

摘要

The neutron spectrum of the fast neutron device in Xi’an Pulse Reactor was measured with multiple foilactivation method and unfolded with SAND-II, the uncertainty of the experimental neutron spectrum was analyzed withMonte Carlo method, its distribution was about 10%～30%.The theory neutron spectrum was simulated and calculated withMonte Carlo method, the bias of the theory spectrum was about 10%. The resolved experiment neutron spectrum was agreewell with the experiment spectrum. The resolved total neutron fluence Φt of the measurement neutron spectrum for the fastneutron device is 2.97×1011n/(cm2.sec), the equivalent 1MeV neutron fluence, Фeq,1MeV is 1.68×1011n/(cm2.sec). The fastneutron fluence Φf with neutron energy above 0.1MeV is 2.01×1011n/(cm2.sec), the epithermal neutron fluence Φepi withneutron energy between 0.4eV to 0.1MeV is 9.75×1010n/(cm2.sec), and the thermal neutron fluence Φth with neutron energybelow 0.4eV is 4.75×108n/(cm2.sec). The gamma ray dose rate of the device was measured with thermoluminescentdetector(7LiF(Mg,Ti)-1007M) which was non-sensitive to neutrons, the measured gamma dose rate of the device was0.35Gy(Si)/s, the uncertainty of the measurement gamma dose was about 30%.The experiment value of Φf / ·Dγ for the fast neutron device is about 5.74×1011 n/(cm2.Gy(Si)). The experiment results prove that the indexes of the device designed weresatisfied well. In the end of the paper, the difference between the experiment and calculation results were analyzed.