The readout electronics for the drift chamber based cosmic ray muon radiography of high-Z materials

The drift chamber based cosmic ray muon radiography prototype whose position resolution is expected to reach 50μm and pixel size expected to reach millimeter consists of three parts, detectors and preamplifiers, readout electronics, data acquisition and image reconstruction. In this paper, the readout electronics which is of high integration, high precision and high reliability with low cost is described. The 16-channel VME board which can measure time and charge is presented. The time measurement is based on the TDC (time-to-digital) chip TDC-GP2. It is shown that all channels have a time precision less than 100ps which demonstrates that the readout electronics meets design requirements.