低气压双维位置灵敏多丝正比室的研制

Development of Low Pressure Position Sensitive Multiwire Proportional Chamber

描述了为在放射性束流线上开展核反应研究而研制的灵敏面积为50mm×50mm的双维位置灵敏的低气压多丝正比室,研制的低气压多丝正比室为穿透式,在真空中使用,工作气压为8mb,透射性好,不干扰束流,放射源测试结果表明,它的x,y方向的位置双径迹分辨为1mm,用放射性束流在束测试结果表明,对30—40MeV的低Z放射性束的探测效率大于80％,适用于中能次级束实验中入射束的定位和反应中产生的带电粒子出射角度的测量。

A low pressure two dimensional position sensitive multiwire proportional chamber (LPMWPC) has been developed for measurements of low Z charged particles from the nuclear reaction induced by radioactive ion beam. The detector has a 50mm x 50mm sensitive area and consists of three grids (X-position cathode Y-position) . The position is determined through delay line readout mode. The detector has good beam transparency and is also adequate to be used in vacuum . The LPMWPC has been tested at a pressure of 800Pa of n-heptane and a bias Voltage of 720V. The test results indicate that the position resolution of the chamber is Δx = Δy = 1mm and detection efficiency is larger than 80 % for the low Z particle at intermediate energies. This kind of chamber has be used to determine the direction of the incident particle .