多丝漂移室阵列是设计中的低温高密核物质测量谱仪(Cooling storage ring External-target Experiment,CEE)上的前角带电粒子径迹探测器,信号读出的一种备选方案是采用传统前置放大器和采样幅度数字转换器(Analog-to-Digital Converter,ADC)来完成信号的放大和获取,该方案结构较简单,成本适中,而且可以处理单根丝上的多重点火信号.为了进一步降低电子学的通道数目,而又不显著影响探测器的性能,研制了一种扇入延迟电路,将漂移室上不同的多根丝信号进行扇入延迟处理,合成为一路信号后再输入到采样ADC的单个通道进行波形采样和数字化.实际的测试结果表明,该电路对信号处理产生的信号能量展宽好于1%,时间晃动好于500 ps,对应的位置分辨好于25μm,满足漂移室径迹探测器阵列对位置分辨小于300μm的要求.%Background:Multi Wire Drift Chamber (MWDC) array is the tracking detector at Cooling storage ring External-target Experiment (CEE) under design at Heavy Ion Research Facility at Lanzhou-Cooling Storage Ring (HIRFL-CSR). The physical goal of CEE aims at the studies of the equation of state of nuclear matter at low temperature but high baryon density. The MWDC array needs a large amount of front end electronics followed by a scalable data acquisition system, which are all costly.Purpose:The aim is to design a readout scheme which can lower the cost but keep the performance of the array rarely degraded, and to test the system and demonstrate the feasibility of the design.Methods: Based on the Flash Analog-to-Digital Converter (ADC) acquisition scheme, a fan-in and delay module has been designed in order to record three signals from X, U and V sense wires simultaneously in each Flash-ADC channel.Results: By this means the total number of channels for MWDC is reduced by 60%. The performance of this fan-in and delay module is tested with a MWDC detector using55Fe X-ray source. The amplitude signal and the timing signal are smeared by less than 1% and 500 ps, respectively.Conclusion:Both specifications show that the fan-in and delay module can be used in MWDC with the event rate ranging in 1?10kHz.
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