Imaging effects due to pixel distortions in CdZnTe detectors—results from the HREXI Calibration Facility

ProtoEXIST2 (P2) was a prototype imaging X-ray detector plane developed for wide-field Time Domain Astrophysics (TDA) in the 5 - 200 keV energy band. It composed of an 8 $\times$ array mm thick, 2cm pixelated (32 32) CdZnTe (CZT) detectors with 0.6 pitch that utilize NuSTAR ASIC(NuASIC) readout. During initial development process leading up to post-flight examination entire plane, distortions expected pixel positions and shapes were observed significant fraction detectors. The HREXI (High Resolution Energetic Imager) Calibration Facility (HCF) designed commissioned improve upon these early experiments rapidly map out characterize non-uniformities defects within CZT planes at resolutions down 50 $\rm \mu$m. Using this facility, sub-pixel level response P2 measured 100 \mu$m resolution analyzed extract evaluate area profile individual pixels, their morphology across comparison previous measurements provide additional characterization. In article, we performance coded-aperture telescope using This investigation will serve as guide selection planes, future implementation 4pi X-Ray Imaging Observatory (4piXIO) mission which aims simultaneous continuous full sky ($\rm 4\pi$ sr) 3-200 band \simeq$ 2 arcmin angular $\simeq$ 10 arcsec source localization, well other, instruments.