用于MRPC的皮秒级时间分辨读出系统研究

MRPC is a new kind of gas detector with good time resolution (30~50ps) and high detection efficiency (95%~99%). It is also capable to work with the counting rate up to hundreds of Hz/cm2 under the avalanche mode, which satisfies the request of the TOF (Time of Flight) detector. At present, the readout electronics for MRPC mainly relies on the solution based on the NINO and HPTDC chip, but its time resolution is limited to 18ps(after calibration). To achieve higher time resolution, the new method with several picoseconds time resolution needs to be researched. Recent literatures show that waveform sampling with switched-capacitor arrays (SCA) has achieved the time resolution below 10 ps. In addition, considering the power, space and budgets, SCA is also very suitable for MRPC readout. We propose a readout electronics solution of MRPC based on TOT（Time Over Threshold） and SCA techniques for high resolution charge and time measurement. This will provide important information for BESIII TOF upgrading project in future.

多气隙电阻板室（MRPC）以其较好的时间分辨（30~50ps）、较高探测效率（95%~99%）和几百Hz/cm2的计数率常被用于飞行时间探测器。传统的基于HPTDC的时间测量方案在校准后虽然可达到18ps的时间分辨，但是随着MRPC探测器工艺技术的改进，若要使得电子学对测量误差的贡献可以忽略(小于10%)，则要求电子学达到皮秒级的时间分辨。新兴的基于开关电容阵列波形采样的时间测量方案在配合一定的校准手段后可以实现了小于10ps的时间分辨，系统集成度方面也非常适合用于MRPC信号读出。本课题利用基于TOT（Time Over Threshold）技术的快放大芯片和基于开关电容阵列波形采样ADC对MRPC的输出信号进行电荷与时间测量，提出一种适用于MRPC探测器的皮秒级时间分辨的多通道读出电子学方案。本课题的研究结果将对今后谱仪电子学升级提供重要依据。

多气隙电阻板室（MRPC）以其较好的时间分辨（30~50ps）、较高探测效率（95%~99%）和几百Hz/cm2的计数率常被用于飞行时间探测器。传统的基于HPTDC的时间测量方案在校准后虽然可达到18ps的时间分辨，但是随着MRPC探测器工艺技术的改进，若要使得电子学对测量误差的贡献可以忽略(小于10%)，则要求电子学达到皮秒级的时间分辨。新兴的基于开关电容阵列波形采样的时间测量方案在配合一定的校准手段后可以实现ps级的时间分辨，系统集成度方面也非常适合用于MRPC信号读出。本课题将基于TOT（Time Over Threshold）技术的快放大和基于开关电容阵列波形采样技术的ADC集成，设计8通道专用芯片，对MRPC的输出信号进行电荷与时间测量，并设计了一种适用于MRPC探测器的皮秒级时间分辨的多通道读出电子学方案。本课题的研究结果将对今后谱仪电子学升级提供重要依据。