Optimization of the spectroscopic response of the Timepix detector

Abstract

The Time over Threshold (TOT) mode of the hybrid semiconductor pixel detector Timepix allows for the direct measurement of the deposited energy in each pixel. Combined with its high spatial resolution the Timepix detector is thus well suited for measurements where the precise position and energy information are required. The energy measurement with the pixel detector is however not easy and the results are degraded by the charge sharing effect. The different electronic response of each pixel requires an energy calibration. Moreover the wide dynamic range (in energy from keV to MeV) which can be registered in each pixel in different applications puts high demands on the analog circuits of the detector chip. The characteristics of the analog circuit of the Timepix are controlled and can be adjusted by a set of detector parameters. The systematic response of the detector with respect to the large number of parameters was not investigated before. In this contribution we present the characterization and optimization of the spectroscopic performance of the Timepix detector by changing and fine tuning the settings of detector parameters using newly developed evaluation method.