RPCs as a medium for digital hadron calorimetry for the linear collider

The purpose of this project is to develop a digital hadron calorimeter (DHCAL) using resistive plate chambers (RPCs) as active medium. RPCs are ideally suited for such a calorimeter: they are simple in design, cheap to build, reliable and robust, and the readout can be segmented into small pads of say 1 cm², as required for a DHCAL at the linear collider. Work on developing these chambers has been underway at Argonne for about two years. Several single-gap and multi-gap chambers operating in avalanche mode have been built and have been tested thoroughly with sources and cosmic rays. Tests with up to 64 pads of 1 cm² each are ongoing. Furthermore, considerable effort is dedicated to the development of the readout system, a challenge by itself given the large number of channels, of order 400K for the prototype and 50×106 for the entire DHCAL.