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arXiv · 1807.04749

Exploring Fine Subpixel Spatial Resolution of Hybrid CMOS Detectors

Evan Bray·Abraham Falcone·Samuel V. Hull·David N. Burrows
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Abstract

When an X-ray is incident onto the silicon absorber array of a detector, it liberates a large number of electrons, which tend to diffuse outward into what is referred to as the charge cloud. This number can vary from tens to thousands across the soft X-ray bandpass (0.1 - 10 keV). The charge cloud can then be picked up by several pixels, and forms a specific pattern based on the exact incident location of the X-ray. We present experimental results on subpixel resolution for a custom H2RG with 36 micron pixels, presented in Bray 2018, and compare the data to simulated images . We then apply the model simulation to a prototype small pixel hybrid CMOS detector (HCD) that would be suitable for the Lynx X-ray surveyor. We also discuss the ability of a small pixel detector to obtain subpixel resolution.

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Evan Bray, Abraham Falcone, Samuel V. Hull, David N. Burrows. 2018-07-12. Exploring Fine Subpixel Spatial Resolution of Hybrid CMOS Detectors. https://doi.org/10.1117/12.2312846

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