Spectrum Techniques ICS-PCI, User Manual

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15
Operation
Preset Time Adjustments
Preset Real Time sets the counting timer to run for actual clocktime and makes no correction for losses due to deadtime
effects. Subsequent acquisition will be automatically stopped by the card at the set time.
Preset Live Time provides automatic correction for counting losses caused by the system deadtime. Events which occur
during the pulse processing cycle are lost to the system so the timer is automatically updated to compensate for these
losses. When operating at excessively high count-rates the deadtime meter will indicate a high value and the real counting
time may be greatly increased. Increasing the LLD setting can help reduce some high deadtime effects.
Click on Settings, click on Presets
Enter the REAL or LIVE time in the correct box. Click on OK, to set adjustment and exit menu.
Both the REAL TIME and LIVE TIME values of a measurement are displayed on the ICS-PCI display screen and updated
during acquisition. The values are saved with the file during data storage.
Related Topics:
Integrals and Preset Counts
Integrals and Preset Counts
When the marker is positioned in a region of interest (ROI), the ICS-PCI software automatically calculates the Gross and
Net area of the region. In order to minimize statistical effects at the ROI endpoints, a 3-point averaging technique is
applied. The contents of channels (n-1), (n), and (n+1) are summed and averaged to derive the content of the endpoint
channel for the net area computation. A linear interpolation is performed between these averaged endpoint values and
counts below this interpolation are subtracted to arrive at the Net area of the peak. Gross counts is the sum of all
channels in the ROI.
Position the marker in the peak of interest. The Gross and Net areas are automatically computed and displayed on the
spectrum screen.