This menu will display plots of (self calibration) Time Dependent Intensity (TDI) and alternating on/off peak intensities versus time. To acquire self-calibration intensity data click the Special Options button in the Acquire window and select the self calibration sample acquisition type.
To acquire alternating on and off-peak data click the Acquisition Option button in the Acquire! Window and check the “Use Alternating On and Off Peak” option. Then click the Count Times button in the Acquire! Window and enter Unknown Count Factors greater than one. The program will automatically acquire on and off-peak data based on the count time and the unknown count factor. This is useful for trace element acquisition when it is desirable to know if the on and off-peak ratios are changing over time.
Note that the extrapolated x-ray intensity and percent change calculated and displayed in this dialog is based on the Y intercept. This is not the method used for the actual Time Dependent Intensity (TDI) element correction. Instead the Time Dependent Intensity (TDI) element correction utilizes a calculation using the log slope of the fitted data.