"Development of 3-dimentinal high resolution track detector"

为了在垂直和平行于阳极丝的方向上获得高分辨率，研制了阳极阴极读出多室漂移室。利用多次散射效应较小的氦-乙烷混合气体进行了原型实验，得到以下结果：1）采用小单元型导线结构，在大气压下获得了优于100 μ m的阳极读出分辨率。尝试了几种不同的操作条件，并通过计算机模拟再现了这些结果。磁场的作用是可控的，氦基气体和氩基气体具有不同的洛仑兹角。2）测量了氦-乙烷（50：50）混合气体的dE/dx数据与入射粒子β nu的关系。相对论里泽是小。3）测量了阴极读出分辨率的角度依赖性，显示了预期的特性。对于正常（50 °），空间分辨率为400 μ m（550 μ m）wqas发病率。为了抑制阴极图像的扩散并获得更好的分辨率，尝试了更短的阳极-阴极间隙。改善了20%。通过改变气体混合物，考察了一次离子密度的影响。观察到定性效果，然而，浅入射角的数据显示与模拟不一致。尽管在了解阴极读出的基本特征方面仍存在未知因素，但所获得的性能足以用于实际应用。沿着基础数据的积累，在碳纤维薄圆柱体和薄铝阴极条的开发方面，在力学问题上取得了进展。这些都是令人满意的，我们有一个良好的前景，为建设的实用模式。

Development of multi-cell drift chamber with anode and cathode readout was made in the purpose of obtaining high resolution in both perpendicular and parallel with anode wires. Proto-tests using a gas mixture of helium-ethane which has less effect of multiple-scattering were done, and the following results were obtained ;1) Using a small cell type wire configuration, anode readout resolution better than 100mum was obtained with an atmospheric pressure. Several different operating conditions were tried and those results were reproduced by computer simulation. The effect of magnetic field was under control, and the helium based gas has different Lorentz angle than that of the argon based one.2) dE/dx data was measured for a mixture of helium-ethane 50 : 50 as a function of beta nu of incoming particle. Relativistic rize was small. Resolution was 10% for minimum ionizing particles by the sampling of 10 layrs.3) Angular dependence in the cathode readout resolution was measured and it showed the caracteristic as expected. Spacial resolution of 400mum(550mum) wqas obtained for normal (50 deg.)incidence. To suppress the spread of cathode images and to obtain better resolution, shorter anode-cathode gap was tried. Improvement of 20% was seen. Effect of primary ion density was examined by changing the gas mixture. Qualitative effect was seen, however, the data for shallow incident angle showed disagreement with the simulation. Even though the unknown factors remained in understanding the basic feature of the cathode readout, obtained performance was good enough for a practical use.Along with the accumulation of the basic data, progress in mechanical issues were made in the developement of thin cylinder with carbon fibers and cathode strips with thin alminum. These were satisfactory and we had a good outlook for the construction of the practical model.