GammaVision
®
v7 (A66-BW) 783620H / 1013
(97)
where
σ
c
is the calibration fit uncertainty and
σ
p
is the calibration counting uncertainty, both discussed in the sections below.
6.12.7.1. Calibration Counting Uncertainty
When an efficiency calibration is performed, the counting uncertainty is calculated and stored in the calibration record. In general, there is an above-the-knee counting uncertainty and a belowthe-knee counting uncertainty, both calculated and saved to the calibration data record.
For polynomial and TCC-polynomial type calibrations, the counting uncertainty above the knee is calculated as the averaged counting uncertainty of all calibration peaks involved, regardless of the knee energy, as shown below:
(98)
where
σ
ci
is the counting uncertainty of the i-th calibration peak, and N is the total number of calibration peaks used. The counting uncertainty below the knee is always set to zero for these two calibration types:
(99)
For all other calibration types, the above-the-knee counting uncertainty is calculated as the averaged counting uncertainty of all the calibration peaks with energy greater than or equal to the knee energy, as shown below:
(100)
where N1 isthe number of calibration peaks whose energies are greater than or equal to the knee energy.
The below-the-knee counting uncertainty is calculated as the averaged counting uncertainty of all the calibration peaks with energy less than the knee energy:
(101)
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