Position readout of MSGC by position encoding into signal pulses

摘要

We are currently developing a new readout method for MSGCs based on a fast ADC system and position encoding in signal waveforms. In this method signal shapes from an MSGC are digitally analyzed to provide the incident positions of individual signals. Signal shapes are varied with the incident position on the MS plate. Both x and y axes can be encoded into one pulse signal for a later analysis in the digital signal processing. To realize the principle, we have fabricated a special type of the MS plate. The MS plate consists of anode strips, cathode electrodes, and grid electrodes placed between the anode and the cathode. No backside electrode is necessary for two dimensional position sensing. Simulation calculations for the ion collection several prototype MS plates were fabricated. A test detector has shown a photopeak for 5.9 keV X-rays. The principle of the position detection has been successfully demonstrated using a fall time measurement of signal pulses.