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stands is not sufficiently accurate, the channel corresponding to that energy might be off by a channel or two. If this is not the correct peak channel, move the cursor to the correct channel, click once on the library peak, and press <Enter>.
NOTE
If the No FWHM Cal checkbox on the Energy Calibration sidebar is marked, the
FWHM calibration is not changed during calibration. This might be desirable when decay of short-lived isotopes in a calibration source results in peaks that are adequate for an energy calibration but whose shape might not be optimal for the FWHM calibration.
To exit the calibration function, click the Energy Calibration Sidebar’s Close button. This will close the calibration function, and the new calibration will be held in memory, available for subsequent spectra gathered on this Detector. To save the calibration to disk, select Save Calibra-
tion... from the Calibrate menu.
5.3.2.6. Other Sidebar Control Commands
The remaining items on the sidebar control menu are Move, Close, Restore, Clear Table, and
Destroy. Destroy clears all energy calibration values. Restore reinstates the internal energy calibration table to the values stored when the calibration function was entered. Clear table erases all the values in the table, but retains the function (energy and FWHM) to be used when the next values are entered. In this way, a recalibration can be done without manual entry of any points. Close exits the Energy... calibration function and saves the current calibration as the working calibration.
5.3.2.7. Using Multiple Spectra for a Single Calibration
To use more than one source (when simultaneous collection is not possible) to make a single calibration:
1) Collect a spectrum with one source or calibrate with this spectrum.
2) Exit the calibration function.
3) Clear the Detector.
4) Collect the spectrum of the second source.
5) Calibrate by adding the new lines to the existing ones (which are retained).
The process can be repeated for additional sources. When completed, the calibration should be saved on disk. The individual spectra can be saved or used in other application software. In addition, the calibrations in the spectra can be updated by recalling each spectrum in turn, recalling the complete calibration, and re-saving the spectrum.
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