HCF (HREXI Calibration Facility): Mapping out sub-pixel level responses from high resolution Cadmium Zinc Telluride (CZT) imaging X-ray detectors [IMA]

http://arxiv.org/abs/2004.03936


The High Resolution Energetic X-Ray Imager (HREXI) CZT detector development program at Harvard is aimed at developing tiled arrays of finely pixelated CZT detectors for use in wide-field coded aperture 3-200 keV X-ray telescopes. A pixel size of $\simeq$ 600 $\mu m$ has already been achieved in the ProtoEXIST2 (P2) detector plane with CZT read out by the NuSTAR ASIC. This paves the way for even smaller 300 $\mu m$ pixels in the next generation HREXI detectors. This article describes a new HREXI calibration facility (HCF) which enables a high resolution sub-pixel level (100 $\mu m$) 2D scan of a 256 $cm^2$ tiled array of 2 $\times$ 2 cm CZT detectors illuminated by a bright X-ray AmpTek Mini-X tube source at timescales of around a day. HCF is a significant improvement from the previous apparatus used for scanning these detectors which took $\simeq$ 3 weeks to complete a 1D scan of a similar detector plane. Moreover, HCF has the capability to scan a large tiled array of CZT detectors ($32cm \times 32cm$) at 100 $\mu m$ resolution in the 10 – 50 keV energy range which was not possible previously. This paper describes the design, construction, and implementation of HCF for the calibration of the P2 detector plane.

Read this paper on arXiv…

A. Basak, B. Allen, J. Hong, et. al.
Thu, 9 Apr 20
30/54

Comments: 27 pages, 19 figures, Accepted for publication in the Journal of Astronomical Telescopes, Instruments, and Systems (SPIE)