Micron resolution of MÖNCH and GOTTHARD, small pitch charge integrating detectors with single photon sensitivity

Abstract

MÖNCH, a charge integrating readout ASIC (Application Specific Integrated Circuit) prototypewith a pixel pitch of 25 μm developed at PSI, allows new imagingapplications in the field of micron resolution and spectral imaging.The small pixel size of this system facilitates charge sharing betweenpixels, which then can be exploited to gain additional informationabout the photon absorption position and photon energy.However, for reconstructing complete images from this information,sufficient hits need to be recorded and therefore acquisition timesare potentially long. We present a fast read-out system, that iscapable of acquiring enough statistics for an image in a few hours incombination with a position reconstruction algorithm, which has thepotential to run in a similar amount of time on a fast computing node.We further present results of experiments with a comparable strip detector (small-pitch GOTTHARD system) showing that with the aid of single photon interpolation algorithms micronresolution is achievable. Additionally, we show that a similar position reconstruction algorithm works in the two dimensional case for MÖNCH.