西安脉冲堆(XAPR)辐照^(40)Ar/^(39)Ar定年样品条件探究  

Research of Xi'an Pulsed Reactor (XAPR) for Irradiation Conditions of ^(40)Ar/^(39)Ar Dating Sample

作　　者：石雅静 刘汉彬[1] 李军杰[1] 张佳[1] 金贵善[1] 韩娟[1] 张建锋[1] 石晓[1] 张万峰[2] 石佳 Shi Yajing;Liu Hanbin;Li Junjie;Zhang Jia;Jin Guishan;Han Juan;Zhang Jianfeng;Shi Xiao;Zhang Wanfeng;Shi Jia(Beijing Research Institute of Uranium Geology,Beijing 100029,China;Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China;Wuhan Second Ship Design and Research Institute,Wuhan 430010,China)

机构地区：[1]核工业北京地质研究院,北京100029 [2]中国科学院广州地球化学研究所,广东广州510640 [3]武汉第二船舶设计研究所,湖北武汉430010

出　　处：《地球科学》2025年第1期88-96,共9页Earth Science

基　　金：核能开发项目(No.测H2301-2-7);国家自然科学基金面上项目(No.41973051)。

摘　　要：国内样品辐照资源有限,可供选择的反应堆数量少,反应堆开启频率低,缺乏对反应堆辐照样品参数的系统研究,在不同程度上制约了^(40)Ar/^(39)Ar定年科研进展,需要开拓新的辐照资源.首次研究西安脉冲堆(XAPR)用于^(40)Ar/^(39)Ar定年样品的辐照条件,通过黑云母标准物质ZBH-25确定中子通量的径向梯度和轴向梯度变化情况,并通过钾盐和钙盐获得反应堆的副反应校正因子.结果表明辐照孔道径向J值变化幅度较小,仅为0.49%,且包含中子通量的峰值,表明样品处于反应堆中心位置进行辐照.辐照孔道轴向中子通量梯度为0.54%/cm,XAPR辐照孔道内的校正因子(^(40)Ar/^(39)Ar)K=0.002 082 6、(^(39)Ar/^(37)Ar)Ca=0.000 776 92、(^(36)Ar/^(37)Ar)Ca=0.000 299 98.对标准物质ZBH-25黑云母进行年龄测定,证明此反应堆满足^(40)Ar/^(39)Ar定年样品的辐照条件,可以作为一个新的辐照源.Domestic sample irradiation resources are limited,with few reactors available,infrequent reactor startups,and a lack of systematic research on the parameters for reactor irradiation samples.These limitations hinder the progress of scientific research in ^(40)Ar/^(39)Ar dating.Therefore,it is essential to develop new irradiation resources.For the first time,the irradiation conditions for ^(40)Ar/^(39)Ar dating samples in the Xi'an Pulsed Reactor(XAPR)were studied.The radial and axial gradient changes in neutron flux were determined using the biotite standard material ZBH-25,and the correction factors for side reactions were obtained using potassium salt and calcium salt.The results indicate that the radial J value of the irradiation channel is 0.49%,and a peak neutron flux,suggesting that the sample is irradiated in the center of the reactor.The axial neutron flux gradient in the irradiation channel is 0.54%/cm,and the correction factors in the XAPR irradiation channel are(^(40)Ar/^(39)Ar)K=0.0020826,(^(39)Ar/^(37)Ar)Ca=0.00077692,(^(36)Ar/^(37)Ar)Ca=0.00029998.The standard material ZBH-25 biotite was dated,confirming that the reactor meets the irradiation conditions for ^(40)Ar/^(39)Ar dating samples and can serve as a new irradiation source.

关 键 词：西安脉冲堆 ^(40)Ar/^(39)Ar定年 辐照条件 中子通量梯度 校正因子 地球化学 

分 类 号：P597[天文地球—地球化学]