Synchrotron measurements of the energy response functions of CdTe Medipix2 MXR detectors with pixel pitches of 110 and 165 μm

Abstract

The energy resolution of photon counting pixel detectors depends strongly on the pixel pitch. Small pixels increase the effects of characteristic X-rays and the sharing of charges between adjacent pixels. To investigate the effects of different pixel pitches, measurements with Medipix2 MXR detectors attached to CdTe sensors with pixel pitches of 110 and 165 μm were carried out at the Topo-Tomo beamline of the ANKA synchrotron at the Karlsruhe Institute of Technology (KIT). Photo peaks are measured at a number of energies and are used to calculate the fraction of events in the photo peak compared to the total. Finally, we investigate the linearity of the energy calibration curves as a function of the pixel pitch. © 2012 IOP Publishing Ltd and Sissa Medialab srl.