TPC气体探测器研究

开展时间投影室（TPC）气体探测器的研制工作：1）设计了探测器漂移区场笼结构,通过设计与优化印刷电路板等梯度势电极的精确位置构建,获得了均匀的电场分布;2）探测器雪崩放大区通过构建3层细丝电极实现;3）探讨了多层多根细丝电极的电场分布计算、电极焊接安装工艺、电极细丝张力维持、探测器不同工作状态转换等工艺技术;4）采用DPC电阻阵列法对探测器的信号读出部分进行简化,实现20路×20路接收电极输出简化为4路输出,并进行了位置刻度试验;5）利用研制的探测器开展了宇宙射线入射信号的测量,获得了真实有效的输出波形,测量波形结果与模拟结果基本一致,并取得了电离事件的有效二维位置分布.本工作可为类似TPC探测器的研制及试验提供经验积累和技术借鉴.

Studies on a TPC gaseous detector

A TPC gas detector was designed and fabricated．Firstly, the field cage was made with printed circuit board plates, which include some accurately located strip electrodes, so as to achieve uniformly distributed electric field in the drift region．Three layers of wire electrodes were assembled in the avalanche region．The identical potential distribution of electric field in different layers of wire electrodes were calculated, and the technologies of wire electrode wielding, tension application on wire electrodes, detector working mode transferring from trigger-on to trigger-off and vice versa were examined．Then, a DPC resistor array was used to simplify readout circuit from 400 to 4 outputs, and the calibrations of array for each node pad were carried out．Lastly, the experiments by the detector for the cosmic ray test was done．The corresponding wave form data agreed well with simulation results, and the transverse positions for these ionization events were also measured．All the work will help a lot to develop this kind of TPC detectors and to do the related experiments．