X-rays frames offer a lot of information about CCD. ⁵⁵Fe sources are traditionally being used for CCD gain and charge transfer efficiency (CTE) measurements. The pixel size of modern scientific CCDs is getting smaller. The charge diffusion causes the charge spread among neighboring pixels especially in thick fully depleted sensors. This enables measurement of the charge diffusion using ⁵⁵Fe X-rays. On the other hand, the usual CTE char- acterization method based on single pixel X-ray events becomes statistically deficient. A new way of measuring CTE using shape and amplitude analysis of X-ray clusters is presented and discussed. This method requires high statistical samples. Advances in test automation and express analysis technique allows for acquiring such statistical samples in a short period of time. The details of our measurement procedure are presented. The lateral diffusion measured using e2v CCD250 is presented and implications for X-ray cluster size and expected cluster shape are discussed. The CTE analysis using total X-ray cluster amplitude is presented. This analysis can reveal CTE problems for certain conditions. The statistical analysis of average X-ray cluster shape is presented. Characteristics X-rays can be used for the whole system absolute calibration. We demonstrate how spectral features of ⁵⁵Fe and ²⁴¹Am rad. sources are used for system linearity measurements.

Date Published: 23 July 2014
PDF: 12 pages
Proc. SPIE 9154, High Energy, Optical, and Infrared Detectors for Astronomy VI, 91540H (23 July 2014); doi: 10.1117/12.2054122

Published in SPIE Proceedings Vol. 9154:
High Energy, Optical, and Infrared Detectors for Astronomy VI
Andrew D. Holland; James Beletic, Editor(s)