Energy weighted imaging of sub pixel contamination in pharmaceutical hard capsule with CdZnTe Timepix3

Abstract

This work investigates the capabilities of a state-of-the-art photon counting CdZnTe Timepix3 detector by combining sub-pixel resolution and energy weighted imaging to resolve and identify metallic particles (< 35 µm) in contaminated pharmaceutical hard capsules. While previous pixelated photon counting semiconductor detectors such as the Timepix or Medipix3 allowed single event analysis only for low photon fluxes that are rather unsuitable for imaging purposes, the new Timepix3 detector allows for the analysis of single events even at high X-ray fluxes due to its data driven data output. The challenges of the project like sufficient charge collection and processing of larger data sets for sub-pixel imaging, the influence of charge sharing and X-ray fluorescence on the spatial and energy resolution as well as 3 different approaches of the energy weighted identification of the metallic powders will be discussed.