Two-Dimensional Position Sensitive Gas Counter with Backgammon Read-Out

Abstract

  A new type of gas counter with a backgammon electrode is developed. The counter can achieve two-dimensional position sensing with the backgammon electrode read-out for one coordinate and the drift time read-out for another coordinate. This counter is designed for use as a transmission type position sensitive detector in a charged particle detecting system that consists of NaI(Tl) crystals. The sensitive region of the counter is about 70x70 mm² and the position resolutions are less then 0.9 mm in full width at half maximum for both coordinates.