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~(115)In是一种重要的活化材料,准确测量它的中子非弹性散射截面数据对中子注量监测具有重要意义。在四川大学原子核科学技术研究所2.5 MV静电质子加速器上,利用核反应D(d,n)~3He产生的单能中子,以~(197)Au作为标准,采用活化法测量了2.95 Me V、3.94 Me V、5.24 Me V能点的~(115)In中子非弹性散射截面。用Monte Carlo程序MCNPX(Monte Carlo N-Particle eXtended)对靶头材料、冷却水层和样品的包层材料等引起的多次散射效应及注量率衰减效应等进行了修正计算,得到最终结果与Loevestam的计算值符合较好,并且实验中可通过减小靶管、靶底衬、水层及样品的包层材料等厚度来减小多次散射效应和自屏蔽效应的影响。
~ (115) In is an important activating material. The accurate measurement of its neutron inelastic scattering cross section data is of great significance for neutron flux monitoring. In the 2.5 MV electrostatic proton accelerator at the Institute of Nuclear Science and Technology of Sichuan University, single-energy neutrons generated by the nuclear reaction D (d, n) ~ 3He were used to measure the activation energy of 2.95 MeV with ~ (197) Au as the standard. The ~ (115) In neutron inelastic scattering cross section of 3.94 Me V, 5.24 Me V energy points. Monte Carlo program MCNPX (Monte Carlo N-Particle eXtended) on the target material, the cooling water layer and the sample cladding material caused by multiple scattering effects and fluence rate decay effect was calculated to obtain the final result and Loevestam’s calculated values are in good agreement, and the effects of multiple scattering effects and self-shielding effects can be reduced in experiments by reducing the thickness of the target tube, target substrate, aqueous layer, and cladding material of the sample.