A MAPS-based Digital Electromagnetic Calorimeter for the ILC

A novel design for a silicon-tungsten electromagnetic calorimeter is described, based on Monolithic Active Pixel Sensors (MAPS). A test sensor with a pixel size of 50x50 um2 has been fabricated in July 2007. The simulation of the physical sensor is done using a detailed three-dimensional charge spread algorithm. Physics studies of the sensor are done including a digitisation algorithm taking into account the charge sharing, charge collection efficiency, noise, and dead areas. The influence of the charge sharing effect is found to be important and hence needs to be measured precisely.