标题： 新构建的塑料闪烁体桶在WASA-FRS实验中的性能以及对多像素光子计数器的辐射损伤效应的评估 显示英文标题

标题： Performance of newly constructed plastic scintillator barrel in the WASA-FRS experiments and evaluation of radiation damage effects on multi-pixel photon counter

摘要： 一种带有多像素光子计数器(MPPC)读出的桶形塑料闪烁计数器已在GSI的第一次WASA-FRS实验活动中开发并运行。该探测器用于测量入射在碳靶上的2.5 GeV质子束引发的反应中发射的带电粒子，并结合1 T磁场中的动量重建进行粒子识别。该探测器的性能，特别是其对能量沉积和时间分辨率的响应，已作为计数率和照射质子总数的函数进行了系统研究。实现了45-75 ps（$\sigma$）的时间分辨率，具体取决于能量沉积。在每单个计数器高达1.35 MHz的高率条件下，保持了稳定性能，信号幅度或时间响应均无显著退化。观察到MPPC的辐射损伤主要表现为信号幅度的减少，在估计的1 MeV中子等效通量为$2.4 \times 10^{10}$cm$^{-2}$的情况下，大约减少了$35\%$。 显示英文摘要

摘要： A barrel-shaped plastic scintillation counter with Multi-Pixel Photon Counter (MPPC) readout has been developed and operated in the first WASA-FRS experimental campaign at GSI. The detector was used to measure charged particles emitted from reactions induced by a 2.5 GeV proton beam incident on a carbon target, providing particle identification in combination with momentum reconstruction in a 1 T magnetic field. The performance of this detector, particularly its response to energy deposition and time resolution, was systematically investigated as a function of count rate and total number of irradiating protons. A time resolution of 45-75 ps ($\sigma$), depending on the energy deposition, was achieved. Stable performance was maintained under high-rate conditions up to 1.35 MHz per single counter, with no significant degradation in either signal amplitude or timing response. Radiation-induced damage to the MPPCs was observed primarily as a reduction in signal amplitude, with approximately $35\%$ decrease at an estimated 1 MeV neutron-equivalent fluence of $2.4 \times 10^{10}$ cm$^{-2}$.