29 August 2017 Modeling and measuring charge sharing in hard x-ray imagers using HEXITEC CdTe detectors
Author Affiliations +
The Rutherford Appleton Laboratory’s HEXITEC ASIC has been designed to provide fine pixelated X-ray spectroscopic imaging in combination with a CdTe or CZT detector layer. Although HEXITEC’s small pixels enable higher spatial resolution as well as higher spectral resolution via the small-pixel effect, they also increase the probability of charge sharing, a process which degrades spectral performance by dividing the charge induced by a single photon among multiple pixels. In this paper, we investigate the effect of this process on a continuum X-ray spectrum below the Cd and Te fluorescence energies (23 keV). This is done by comparing laboratory measurements with simulations performed with a custom designed model of the HEXITEC ASIC. We find that the simulations closely match the observations implying that we have an adequate understanding of both charge sharing and the HEXITEC ASIC itself. These results can be used to predict the distortion of a spectrum measured with HEXITEC and will help determine to what extent it can be corrected. They also show that models like this one are important tools in developing and interpreting observations from ASICs like HEXITEC.
Conference Presentation
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Daniel F. Ryan, Daniel F. Ryan, Steven D. Christe, Steven D. Christe, Albert Y. Shih, Albert Y. Shih, Wayne H. Baumgartner, Wayne H. Baumgartner, Matthew D. Wilson, Matthew D. Wilson, Paul Seller, Paul Seller, Jessica A. Gaskin, Jessica A. Gaskin, Andrew Inglis, Andrew Inglis, } "Modeling and measuring charge sharing in hard x-ray imagers using HEXITEC CdTe detectors", Proc. SPIE 10397, UV, X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XX, 1039702 (29 August 2017); doi: 10.1117/12.2274419; https://doi.org/10.1117/12.2274419


CMOS digital pixel sensors: technology and applications
Proceedings of SPIE (April 15 2014)
Compact hard x-ray imaging system with a large FOV
Proceedings of SPIE (July 26 2016)
Hard x-ray imager for the NeXT mission
Proceedings of SPIE (June 14 2006)
Broadband x-ray imaging mission NeXT
Proceedings of SPIE (March 10 2003)

Back to Top