18
The “Cancel” button will only be enabled when the current ROI set has been altered or edited in any way since
it was last saved. Using this function will re-load the current ROI set as it was last saved.
The “New ROI Set” button clears the current ROI set from URSA-II MCA (if it has not been saved, you will be
given the opportunity to do this first) so that a new ROI set can be created. You will be prompted to first name
the ROI set, which you must do in order to continue.
Efficiency
This displays the Efficiency Calibration Panel. This efficiency calibration is based on an ROI set, but the same
calibration is also used when performing peak- or library-based spectrum analyses. An ROI set, therefore, must
be created and/or loaded before this panel is available. Efficiency calibrations are unique to specific URSA-II/
ROI file/Detector combinations.
“Current ROI Set Name:” displays the filename of the currently loaded ROI set. Note: A small display will
appear below “Current ROI Set Name:” (not shown in the display above) that flags the fact that the current ROI
set has been altered using the ROI Panel but not yet saved. It is not recommended that an efficiency calibration
be performed using an unsaved ROI set.
If the “Allow Edit” box is checked, the controls on this panel will be unlocked for editing. If this box is not
checked, the data for the last calibration can be viewed but not altered.
The arrow buttons will change the currently selected specific ROI within the greater ROI set and the data
on this panel will reflect only that specific ROI, as will any modifications. The currently selected ROI will be
displayed in fuchsia.
The gray boxes display specific ROI data, including the efficiency (as a percentage of counts detected per
disintegration) if a calibration has been previously performed.
The “Assign ROI as Unknown” checkbox allows a specific ROI within an ROI set to be designated as one that is
not contained in the efficiency calibration source being used.
The “Associated Nuclide” control contains a dropdown list of all enabled nuclides in the current library. Prior
to performing an efficiency calibration, a nuclide must be assigned to each ROI within the ROI set by clicking
on one of the items in the list. If the needed nuclide is not in this list, the library must be edited to enable this
nuclide.
The “Associated Peak” control contains a dropdown list of all enabled peaks (for the nuclide selected as the
associated nuclide) in the current library. Prior to performing an efficiency calibration, one of these peaks
must be assigned to each ROI within the ROI set by clicking on one of the items in the list. If a needed peak or
multiplet is not on the list, the library must be edited to enable or add this peak or multiplet.
