暗物质粒子探测器径迹重建方法的研究
发布时间：2018-10-05 08:10
【摘要】：暗物质粒子探测器(DAMPE,Dark Matter Particle Explorer)旨在通过对空间高能粒子的大能量范围、高能量分辨和高空间分辨的观测间接探究暗物质的存在和分布.径迹重建是利用探测器不同位置探测通道的观测结果重建高能粒子入射位置和方向,其结果的准确性决定了探测器的空间分辨本领.暗物质粒子探测器径迹重建主要依靠其中的硅阵列探测器(STK,Silicon Tracker)和BGO(锗酸铋,Bi4Ge3O12)量能器两个子探测器的观测.结合两者的设计原理和结构,利用多次束流试验和地面宇宙线实验数据细致探讨了径迹重建的基本方法,主要包含3个基本步骤:径迹点的选取,径迹点的拟合以及最佳径迹的判选.粒子在每层STK和BGO晶体中往往留下多个击中点,首先给出了一种利用BGO重心法得到粒子粗略径迹并以此限定STK径迹点的方法.接着对于选定的一组可能的STK径迹点尝试了Kalman滤波和直线最小二乘拟合两种拟合法,并发现两种方法分别独立得到比较一致的结果,从而验证了结果的有效性.最后,对于重建得到的多条可能径迹,讨论了一些利用BGO量能器和STK结果进行联合判选的方法.利用提出的径迹重建方法对多次束流试验数据的处理表明,暗物质粒子探测器的空间分辨完全达到了设计要求.
[Abstract]:The dark matter particle detector (DAMPE,Dark Matter Particle Explorer) aims to explore the existence and distribution of dark matter indirectly through the observation of large energy range, high energy resolution and high spatial resolution of high energy particles in space. Track reconstruction is to reconstruct the incident position and direction of high-energy particles by using the observation results of probe channels at different positions. The accuracy of the results determines the spatial resolution of the detectors. The track reconstruction of dark matter particle detector mainly depends on the observation of silicon array detector (STK,Silicon Tracker) and BGO (bismuth germanate Bi4Ge3O12) calorimeter. Combined with the design principle and structure of the two methods, the basic methods of track reconstruction are discussed in detail by using the data of multiple beam tests and cosmic ray experiments on the ground, which mainly include three basic steps: the selection of track points. The fitting of track points and the selection of the best track. Particles often leave more than one hit point in each layer of STK and BGO crystals. Firstly, a method to obtain the rough track of particles by using BGO barycenter method and to define the STK track point is presented. Then, Kalman filtering and linear least square fitting are used to fit a set of possible STK track points, and the two methods are found to be independent of each other to obtain relatively consistent results, thus validating the validity of the results. Finally, for several possible tracks reconstructed, some methods of joint selection using BGO calorimeter and STK results are discussed. It is shown that the spatial resolution of the dark matter particle detector fully meets the design requirements by using the proposed track reconstruction method to deal with the data of multiple beam experiments.
【作者单位】： 中国科学院紫金山天文台;中国科学院暗物质与空间天文重点实验室;中国科学院大学;
【基金】：国家自然科学基金项目(11303105、11303106、11303107)资助
【分类号】：P145.9
，
本文编号：2252640
[Abstract]:The dark matter particle detector (DAMPE,Dark Matter Particle Explorer) aims to explore the existence and distribution of dark matter indirectly through the observation of large energy range, high energy resolution and high spatial resolution of high energy particles in space. Track reconstruction is to reconstruct the incident position and direction of high-energy particles by using the observation results of probe channels at different positions. The accuracy of the results determines the spatial resolution of the detectors. The track reconstruction of dark matter particle detector mainly depends on the observation of silicon array detector (STK,Silicon Tracker) and BGO (bismuth germanate Bi4Ge3O12) calorimeter. Combined with the design principle and structure of the two methods, the basic methods of track reconstruction are discussed in detail by using the data of multiple beam tests and cosmic ray experiments on the ground, which mainly include three basic steps: the selection of track points. The fitting of track points and the selection of the best track. Particles often leave more than one hit point in each layer of STK and BGO crystals. Firstly, a method to obtain the rough track of particles by using BGO barycenter method and to define the STK track point is presented. Then, Kalman filtering and linear least square fitting are used to fit a set of possible STK track points, and the two methods are found to be independent of each other to obtain relatively consistent results, thus validating the validity of the results. Finally, for several possible tracks reconstructed, some methods of joint selection using BGO calorimeter and STK results are discussed. It is shown that the spatial resolution of the dark matter particle detector fully meets the design requirements by using the proposed track reconstruction method to deal with the data of multiple beam experiments.
【作者单位】： 中国科学院紫金山天文台;中国科学院暗物质与空间天文重点实验室;中国科学院大学;
【基金】：国家自然科学基金项目(11303105、11303106、11303107)资助
【分类号】：P145.9
，
本文编号：2252640
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