APPENDIX D. CALCULATIONS
D.1. The Nuclide Report
The Nuclide Report displays the activity of up to 9 user-selected peaks. Once the report is set up
you can view the Nuclide Report at any time. The peak area calculations are the same as the
calculations in MAESTRO and other ORTEC software, so the Report contents can be duplicated
using the spectra stored in the computer. The calculated value is computed by multiplying the
net peak count rate by a user-defined constant. If the constant includes the efficiency and
branching ratio, the displayed value will be activity. The nuclide label and the activity units are
entered by the user.
The report has this format:
Nuclide
keV
uCi/m2
±%
CO-60
1332.5
1.21E+01
10.2
CO-60
1173.2
1.09E+01
12.3
CO-57
122.1
1.48E+00
86.2
D.1.1. Calculations
These are the calculations used to generate the Nuclide Report’s
Activity
,
Uncertainty
, and
Peak
values.
Activity
is calculated as follows:
NucCoef
is normally the inverse of efficiency times the branching ratio. Note that the
efficiency is the ABSOLUTE counting efficiency for the source-detector geometry being
used. Thus, in order to get meaningful activity results, as in any counting situation, you
need to have efficiency factors which are appropriate to the actual counting geometry. If
NucCoef
is set to 1, you will get peak count rate on the display.
LiveTime
is the current live time.
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