Two-Dimensional Read out of Large Muon Drift Tubes

测试了利用锯齿形延迟线测量漂移管敏感线沿着方向坐标的可行性。用截面为10 cm × 5cm、长140 cm的矩形铝管制作了两个原型室。在该管中，腔室（类型-1）在中心处具有感测线，并且在底部平面上具有移位的锯齿形延迟线带。类型2在垂直于平面的中心处具有相同的条带，并且在由条带分隔的截面的中心处具有两个感测线。感应线是镀金钨100<mu>米直径。延迟线带光刻在覆铜Kapton带的两侧。阻抗为60<OMEGA>，延迟时间为3.2ns/cm，总延迟时间为450 ns。在延迟线上感应的脉冲高度约为感测线的1/10。然后，该室在有限流光模式下操作。使用70%氩气和30%异丁烷的混合物。在4.3kV时，检测效率为98%。Ru的准直电子通过电离室到达闪烁计数器。一个带电粒子从传感线和延迟线的两端产生三个信号。用10位、1 ns分辨率的TDC测量了这些信号的时间。在两种分布的延迟线中，感生脉冲的传播速度均为3.28 0.01ns/cm.沿感测线的位置精度沿着为4.7 mm（类型1）和2.7 mm（类型2）的sigma。另一个坐标是通过测量感测线和闪烁计数器之间的时间差来获得的。位置精度为1 mm的sigma。使用100 MHz FADC测量来自末端的脉冲高度以测量诱导脉冲的衰减。得到的衰减因子为168 cm。

The feasibility of using zig-zag delay line to measure the coordinate along the sense wire from a drift tubes was tested. Two prototype chambers made of a recutangular aluminium tube with the cross section of 10cmx5cm and length of 140cm have been constructed. In this tube a chamber(type-1) has a sense wire at the center and a shifted zig-zag delay line strip on the bottom plane. Type-2 has the same strip at the center vertical to the plane and two sense wires at the center of the section separated by the strip. The sense wire is gold plated tungsten 100 <mu> m diameter. The delay line strip is photo-etched on both sides of copper-cladded Kapton strip. The impeadance is 60 <OMEGA> , the delay time is 3.2ns/cm and the total delay time is 450ns. The pulse height induced on the delay line is about 1/10 of the sense wire. Then, the chamber operated in the limitted-streamer mode. A mixture of 70% Argon and 30% iso-Butane was used. The detection efficiency was 98% at 4.3kV. Well-collimated electrons of Ru come through the chamber to scintillation counter. A charged particle generates three signals from sense wire and the two ends of the delay line. Times of these signals were measured by 10 bit, 1ns resolution TDC. The propagation velocity of the induced pulses in both distributions of the delay line is obtained to be 3.28 <+!-> 0.01ns/cm. The position accuracies along the sense wire are sigma of 4.7mm(type-1) and 2.7mm(type-2). The other coordinate was obtained by measuring the time difference between the sense wire and the scintillation counter. A position accuracy is sigma of 1mm. Pulse heights from the ends were measured using 100MHz FADC to measure attenuation of induced pulse. The attenuation factor obtained is 168cm.