权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on Measurements of Nuclear Data for Transmutation of Actinide Elements using Lead Slowing-down Spectrometer

铅减速谱仪测量锕系元素嬗变核数据的研究

基本信息

批准号：
06452430
负责人：
KOBAYASHI Katsuhei
金额：
$ 4.54万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06452430/
关键词：
Lead Slowing-down Spectrometer Actinide Elements Chemical Purification ^<241>Am (n, f) Reaction Cross Section ^<243>Am (n, f) Reaction Cross Section ^<242m>Am (n, f) Reaction Cross Section Double Fission Chambers ^<237>Np (n, gamma) Reaction

项目摘要

A lead slowing-down spectrometer was installed coupled to the 46 MeV electron linac at Research Reactor Institute, Kyoto University (KURRI). Characteristics of the Kyoto University Lead Slowing-down Spectrometer (KULS) were measured for (1) the relation between neutron slowing-down time t (mus) and energy E (keV) (E=190/t^2 in Bi hole and E=156/t^2 in Pb hole), (2) the energy resolution (-40% in Bi and Pb holes), and (3) the neutron energy spectrum by the neutron TOF method. The results obtained by the MCNP code were in general agreement with these experimental ones.The KULS has been applied to the fission cross section measurements of Am-241, Am-243 and Am-242m relative to that of U-235 from -0.1 eV to -10 keV,making use of the back-to-back type double fission chambers. For Am-214, Dabbs and ENDF/B-VI data are in good agreement with the present measurement. The JEND L-3.2 data are smaller by a factor of 2 between 10 and 200 eV.The ENDF/B-VI data for Am-243 are lower between 15 and 60 eV,and the JENDL-3.2 are lower in general above 100 eV.It has been found that the preliminary result for the Am-242m (n, f) reaction is close to the ENDF/B-VI and the JENDL-3.2 data. Thermal neutron cross sections for Am-241 and Am-243 have also been measured in a standard Maxwellian distribution spectrum field.Finally, aiming at the measurement of capture cross section for MA nuclides, the experimental investigation for Np-237 sample (-2 mg) has been performed with the KULS.Due to the comparable background counts to the foreground ones, the capture events from the sample have scarecely been detected with an Ar-gas proportional counter.

在京都大学研究堆研究所的46 MeV电子直线加速器上安装了铅慢化谱仪。测量了京都大学铅慢化谱仪（KULS）的特性：（1）中子慢化时间t（μ s）与能量E（keV）的关系（Bi孔E=190/t^2，Pb孔E=156/t^2），（2）能量分辨率（Bi和Pb孔为~ 40%），（3）中子飞行时间法中子能谱。MCNP程序的计算结果与实验结果基本一致，KULS已应用于Am-241、Am-243和Am-242 m相对于U-235在-0.1 ~-10keV范围内的裂变截面测量。对于Am-214，Dabbs和ENDF/B-VI数据与目前的测量结果符合得很好。Am-243的ENDF/B-VI数据在15 - 60 eV之间较低，而JENDL-3.2通常在100 eV以上较低。已发现Am-242 m（n，f）反应的初步结果接近ENDF/B-VI和JENDL-3.2数据。最后，针对MA核素俘获截面的测量，利用KULS对Np-237样品（~ 2 mg）进行了实验研究，由于本底计数与前景计数相当，因此本底计数与前景计数的测量结果基本一致。来自样品的捕获事件很少用Ar-气体正比计数器检测到。