Weighting potentials in CdZnTe /spl gamma/-ray detectors with segmented electrodes

Tousignant, O.; Hamel, L. A.; Vasilevski, D.

doi:10.1109/23.903852

Cited by 3 publications

(1 citation statement)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the weighting potential ( ) a transition from unity to zero must occur in the gaps between the selected anode and its neighbours. A boundary condition involving the gradient and the surface normal is commonly applied [ 31 , 39 , 43 , 44 ], represented by alternative B1. The inverse-distance weighting [ 45 ] method (alternative B2) has not been used previously, and was introduced to obtain way to parametrise and adjust the steepness of the lateral sides of the weighting potential and CIE. Additionally, a scale factor was introduced for alternative B2 to force the weighting potential to reach zero at the edge of the neighbouring anode or at some position within the gap, thus allowing for adjustment of the "width" of the anode’s sensitive area.…”

Section: Methodsmentioning

confidence: 99%

Monte Carlo modelling of a compact CZT-based gamma camera with application to 177Lu imaging

et al. 2022

View full text Add to dashboard Cite

Background Semiconductor gamma-camera systems based on cadmium zinc telluride (CZT) detectors present new challenges due to an energy-response that includes effects of low-energy tailing. In particular, such energy tails produce effects that need to be considered when imaging radionuclides with multiple emissions such as $$^{177}{\mathrm {Lu}}$$ 177 Lu . Monte Carlo simulation can be used to investigate the behaviour of such systems and optimise their use, provided that the detector model closely reflects the real physical detector. The aim of this work is to develop a CZT model applicable for simulation of CZT-based gamma cameras. Methods The equations describing the charge transport and signal induction are considered in three dimensions and are solved numerically, and the CZT model is then realised by coupling the detector-response to the photon-transport handled by the SIMIND Monte Carlo program. The CZT model is tuned to reproduce experimentally measured energy spectra of a hand-held gamma camera system for multiple radionuclides ($$^{99\mathrm {m}}{\mathrm {Tc}}$$ 99 m Tc , $$^{123}{\mathrm {I}}$$ 123 I and $$^{177}{\mathrm {Lu}}$$ 177 Lu ) and parallel-hole collimators (MEGP, LEHR) as well as an uncollimated system. Results Overall, the model results agree well with measurements across the range of experimental conditions. The applicability of the model is demonstrated by separating energy spectra into components to investigate the interference of high-energy photons on lower energy-windows, where pronounced effects of low-energy tailing for $$^{177}{\mathrm {Lu}}$$ 177 Lu are observed. Conclusions The developed model provides understanding of the specifics of the camera response and is expected to be helpful for future optimisation of gamma camera applications.

show abstract