A Thin Multiwire Proportional Chamber For Imaging With Uv-Light, X-Rays And Gamma-Rays

A thin multiwire proportional chamber of 5 x 5 cm2 active area has been used for imaging with UV light, X-rays and gamma rays. The slight photosensitivity of Sn-Pb cathode strips permitted imaging of a light bulb filament. Rontgen images of a wrench and a chicken wing have been made with X-rays converted in the chamber gas. An example of the improvement of image quality, obtained by processing the computer stored data, is presented. For 511 keV gamma rays, a 0.1 nun thick Pb layer on the cathode strips has been used as a converter. With two chambers in coincidence, a three-dimensional distribution due to two positron point sources is obtained. Results are given for the measured position resolutions, the efficiencies and, in the case of positron emission tomography, also for the timing resolution.