减小活性靶时间投影室开放式场笼边缘效应的研究

Active Target Time Projection Chamber (AT-TPC) is a novel detector system developed in recent years for the frontier research in the field of low and intermediate energy nuclear physics. AT-TPC usually uses open field cage. At present, there is a lack of research on open field cage at home and abroad. Most of the field cages used in current experiments are developed from traditional closed field cage of TPC and lack of targeted structural optimization. It is found that the edge effect of open field cage is very obvious in the experiment, which results in distortion of the measured particle track. Based on three basic types of open field cage models, this project plans to systematically study the factors affecting the open field cage electric field by changing the parameters of the field cage. Finally, a general optimization scheme and a personalized optimization scheme for different open cages are proposed to reduce the edge effect of open cages. According to the optimized scheme, TPC detector is planned to be built to verify the effectiveness of the scheme. The optimization scheme is helpful to improve the performance of AT-TPC, and provides a reference for AT-TPC to be built at home and abroad.

活性靶时间投影室(AT-TPC)是近年来发展起来的用于中低能核物理前沿研领域究的新型探测器。AT-TPC通常采用开放式场笼，目前国内外对开放式场笼的研究比较缺乏，当前实验中采用的场笼多是由传统TPC封闭式场笼发展而来，缺乏针对性的结构优化，实验中发现这种开放式场笼边缘效应非常明显，造成测量得到的粒子径迹发生扭曲。本项目计划以三种基本类型的开放式场笼为基础，通过改变场笼各种参数，定量化系统的研究影响开放式场笼电场的各种因素，最终提出适用不同开放式场笼的通用优化方案以及个性化优化方案，以期减小开放式场笼的边缘效应。并计划根据优化方案，搭建TPC探测器，通过实验验证该方案的有效性。该优化方案有助于提高AT-TPC性能，为国内外将要建造的AT-TPC提供参考。

活性靶时间投影室是近年来发展起来的用于中低能核物理前沿研领域究的新型探测器，该探测器通常采用开放式场笼设计，场笼内电场主要受到场笼外部强电场、场笼电极布局、场笼周期性结构破坏三种因素影响，不同因素影响的范围和程度各不相同。通过改变场笼电极与探测器外壳的距离、电极中心距、电极宽度、电极厚度，增加半电极结构、局部镜像电极等方式，可以影响上述的一种到多种因素。本项目首先通过计算电场分布评估各个参数对电场的影响程度及其局限性，总结出各种开放式场笼的优化设计方案，然后通过电子输运及激光径迹测试，验证优化效果。本项目结果可以为为不同实验中探测器场笼的设计提供优化指导，简化探测器场笼设计，提高时间投影室性能。