X-ray Absorption in Detector Windows
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The X-rays can be absorbed in the detector window. For detectors with both Be and ultra-thin windows, the absorption in the window material must be considered.

For windowless detectors, the detection performance will extremely be degraded by the formed ice layer on the crystal. Table 1733 lists the dependence of relative detection efficiency, for some low energy X-ray lines, on ice layer thickness. This relative detection efficiency is defined by ε'/ε. Here, ε' is the detection efficiency modified by the ice layer, and ε is the detection efficiency in the absence of the ice layer.

Table 1733. Dependence of relative detection efficiency (ε'/ε), for some low energy X-ray lines, on ice layer thickness (t). [1]
t(nm) B Kα C Kα N Kα O Kα Si Kα Ni Lα
100 0.8620 0.9473 0.9776 0.9893 0.9909 0.9414
500 0.4760 0.7628 0.8930 0.9478 0.9552 0.7395
1000 0.2266 0.5818 0.7974 0.8983 0.9124 0.5469





[1] D. G. Rickerby, Barriers to energy dispersive spectrometry with low energy X-rays, Microbeam and Nanobeam Analysis, edited by Daniele Benoi, 1996.