GBS Elektronik MCA-527 - Manual (Page 38)

MCA527
38
Figure 20: Measuring Cs137 with different PZC settings
Left: Measured Cs137 peak with correct settings. The calculated ration of
FWTM/FWHM is 1.91, which is reasonably close to the 1.82 expected
from a gaussian distribution.
Right: Spectrum without jitter or PZC compensation. As the jitter error has a
rectangle like distribution, the FWTM/FWHM ratio is significantly smaller
here and resolution is generally worse. The wrong pole zero does not
really affect as the count rate is very low.
Figure 21: Measuring Cs137 with different PZC settings, jitter correction always on
Left: Wrong pole zero has the worst effect with higher count rates. Here the
characteristic low energy tailing typical for under-pole-zero can be seen,
and the count FWTM/FWHM ratio is very high.
Right: Too high pole zero setting causes tailing on the high energy side of the
peak