大面积闪烁光纤阵列探测器的在束测试

In-Beam Test of Large Area Scintillating Fiber Array Detector

摘要: 利用70 AMeV ²⁶Mg初级束流及其产生的次级束流，在兰州重离子加速器放射性次级束流线（RIBLL）终端测试了大面积闪烁光纤阵列探测器(LASFA)探测单元的时间分辨和位置分辨能力。利用70 AMeV ²⁶Mg初级束流测试得到的时间分辨约为128 ps，对应的位置分辨约为10 mm；利用次级束流测试得到的时间分辨约为158 ps，对应的位置分辨约为13 mm，具有很好的时间分辨和空间角分辨能力。结合RIBLL的ΔESi探测器，给出了ΔE_Si-TOF二维谱，并将测试结果与RIBLL的粒子鉴别系统进行详细比较。结果表明，大面积闪烁光纤阵列作为轻带电粒子的飞行时间终止探测器，性能优于RIBLL上采用的时间拾取探测器，可更清楚地鉴别次级束流。

Abstract: The time resolution and spatial resolution of the large area scintillating fiber array (LASFA) detector were tested with beam at terminal of radioactive ion beam line in Lanzhou (RIBLL). The results show that LASFA’s time resolution and spatial resolution are very good. The time resolution is about 128 ps, the spatial resolution is about 10 mm for 70 AMeV ²⁶Mg beam, and the time resolution is about 158 ps, the spatial resolution is about 13 mm for RNB fragments. Combining ΔESi detector at RIBLL, the ΔE_Si-TOF spectra are given. As particle flying time stop detector, the LASFA’s property is better than that of time acquisition system on RIBLL.