Flat Top
Sets the flat top portion of the digital filter time response. The flat top matches the fil-
ter to the detector charge collection characteristics to minimize the effects of ballistic
deficit. The flat top time can be selected from 21 flat top selections ranging from 0 to 3
µ
s.
Acquisition Window Adjust Screen
The following section describes those parameters for the 9660 that can be accessed
from the Adjust dialog screen. Note that the Adjust screen for a given device may ac-
tually be composed of several screens, which are accessed by using the
Next/Prev
pushbuttons.
Stabilizer Parameters
The Stabilizer settings screen (Figure 11) for the 9660 contains the following controls.
Gain Centroid
Sets the centroid (in channels) of the reference peak at the high end of the spectrum for
gain stabilization.
Gain Window
Sets the width (in channels) of the upper and lower sampling windows on either side
of the gain reference peak.
Gain Spacing
Sets the spacing (in channels) between the upper and lower sampling windows. The
windows should be placed so that a shift in the reference peak reflects a significant
change in count rate through the window. For broad peaks, the spacing should be set
so that the windows’ edges are not on the flat part of the peak.
Chapter 3 - Genie™ 2000 User Interface and Controls
14
Model 9660-9660A ICB Digital Signal Processor
Figure 11 Adjust Screen's Stabilizer Settings
