Conceptual design of a collimator for the neutron emission profile monitor in JT-60SA using Monte Carlo simulations.
Conceptual design of a collimator for the neutron emission profile monitor in JT-60SA using Monte Carlo simulations.
复制标题
使用蒙特卡罗模拟对 JT-60SA 中子发射轮廓监测器准直器进行概念设计。
DOI：
10.1063/5.0025902
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
N. Oyama
中科院分区：
文献类型：
--
作者：
S. Sumida;K. Shinohara;T. Nishitani;K. Ogawa;T. Bando;A. M Sukegawa;M. Ishikawa;E. Takada;A. Bierwage;N. Oyama
使用蒙特卡罗 N 粒子输运代码通过蒙特卡罗模拟检查 JT-60SA 中新型中子发射轮廓监测器的准直器的材料和结构。首先，比较各种材料组合的屏蔽性能，以确定对中子和伽马射线均具有高屏蔽性能的组合。研究发现，由硼酸化聚乙烯和铅组成的准直器对中子具有较高的屏蔽性能。此外，当将径向厚度为0.01m的导管插入准直管时，可以获得对伽马射线的高屏蔽性能。其次，我们证明，通过安装适合主准直器块和托卡马克装置之间可用的有限空间的细管状延伸结构，可以将空间分辨率提高到所需水平。最后，讨论了满足目标空间分辨率（<等离子体短半径的10%）和目标计数率（105 cps 数量级）的准直器结构。
Materials and structures of a collimator for a new neutron emission profile monitor in JT-60SA are examined through Monte Carlo simulations using the Monte Carlo N-Particle transport code. First, the shielding properties of various material combinations are compared in order to determine a combination with high shielding performances against both neutrons and gamma-rays. It is found that a collimator consisting of borated polyethylene and lead has a high shielding performance against neutrons. Moreover, a high shielding performance against gamma-rays is obtained when a lead pipe with a radial thickness of 0.01 m is inserted into a collimation tube. Second, we demonstrate that it is possible to improve the spatial resolution to a desired level by installing a thin tubular extension structure that fits into the limited space available between the main collimator block and the tokamak device. Finally, the collimator structures that meet both the targeted spatial resolutions (<10% of the plasma minor radius) and the targeted counting rate (105 cps order) are discussed.