Spectrum Techniques ICS-PCI, User Manual

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Energy Calibrate...
The energy calibration feature allows the marker to read directly in energy units.
One Automatic and two Manual calibration functions are possible - a 2-point linear, or a 3-point quadratic fit.
In order to perform an energy calibration, it is first necessary to acquire a spectrum using known isotopes. Cs-137
together with Co-60 works well for many applications, producing gamma lines at 32 keV, 662 keV, 1173 keV and 1332
keV.
2-Point Cal or 3-Point Cal
Select 2-point or 3-point mode and enter the calibration units to be used, (KeV or MeV). Position the marker at the
channel with the maximum counts of the first peak and enter the peak energy value. Move the marker to the high point on
the second peak to be used for the calibration, enter energy number. If a 3-point calibration is required, continue by
moving the marker to the peak channel of the third peak, enter its energy and click OK. The system will now be calibrated
and the marker position will read directly in energy.
If ROI's are set around each peak used in the calibration, it is necessary only to place the marker in the ROI for the peak.
The software automatically calculates the peak centroid and uses this value for the peak position in the calibration routine.
To return to the channel number mode, click on Settings, click on Uncalibrate.
Energy Calibration may also be selected using the right mouse button.
Auto Calibrate...
The automatic calibration feature requires a Cs-137 source to calibrate the instrument with a conversion gain of 1024.
The automatic calibration will determine the coarse and fine gain settings as well as the high voltage settings and will fit
the peaks into a range of 0 to 1024 KeV. Once computed, the calibration coefficients are automatically adjusted for other
conversion gains. If a range other than 1024 KeV is needed, manual 2 or 3 point calibration must be performed.