| X-Ray Detector Performance Parameters Defined | |
| Resolution | Full width at half maximum (FWHM) of the MnKa X-ray peak expressed in electron volts (eV). Usually measured using a Fe-55 radioactive source at a count rate of less than 1000 cps so that an optimum peaking time of 40us or more can be used in the processing electronics. |
| Peak to Background Ratio | Measured using the MnKa line at optimum resolution conditions. Defined as the ratio between the counts in the peak channel of the MnKa line and the average background between 0.9 and 1.1 keV. |
| Tail Factor |
The tail factor is a measurement of the charge collection efficiency of the crystal. If any charge generated during an X-ray interaction is not collected properly it will result in an event which has less energy than the true x-ray energy. This gives rise to a 'tail' on the low energy side of the X-ray peak. The 'tail factor' is measured using the MnKa peak at optimum resolution. It is defined as the percentage ratio of the average counts per channel in the region between the MnKa peak and the corresponding escape peak, bounded by points 3.71*sigma below and above them respectively, and the gaussian fitted peak height of the MnKa line. Please CLOSE this window to return to the current page
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