Canberra Lynx DSA, Руководство пользователя

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Chapter 5 Web-Based Operations
114 Lynx DSA User's Manual - 9240227J
2. With the Lynx acquiring data in PHA mode, and a sample on the detector,
select the energy peak to be used as a reference by the stabilizer. For best
results, the peak should be located in the upper half of the spectrum. The
reference peak should be isolated from other energies as much and as far as
possible.
3. Once the reference peak has been identified, enter the reference peak's center
channel into the stabilizer's Centroid control. With Mirion's Genie Gamma
Analysis application, the Centroid channel can be read directly from the
Marker Info page provided that the left and right markers surround the
reference peak. For best results the reference peak should be well defined,
with sufficient count rate to provide at least 2:1 peak to background ratio.
4. The selection for the Spacing value and Window width largely determine the
effectiveness of the stabilizer. The window width should provide for
sufficient counting statistics but exclude interference from adjacent peaks.
The spacing should provide sufficient separation between the sampling
windows to strategically position the windows on the peak where a change in
data rate will result in maximum effect detected by the algorithm, such as on
the shoulders of the peak. Spacing values that are approximately 50% of the
FWHM and window width that are approximately 80% of the FWHM are
typical settings. With Mirion's Genie Gamma Analysis application, the
FWHM can be read directly from the Marker Info page provided that the left
and right markers surround the reference peak. Please note that the value
reported by Genie is in energy units, and manual conversion to channels may
be necessary.
5. For most applications, the Ratio Mode should be set to
Auto
. The Auto mode
directs the stabilization algorithm to automatically calculate the reference
using the given windows and spacing parameters, then manage the correction
as necessary based on the data being acquired. Manual mode should only be
used to allow a client application to calculate the reference and pass it to the
Lynx.
6. The Rate Divider determines the aggressiveness of the algorithm, with lower
values being most aggressive. Typically this is determined by the expected
rate of temperature changes in the Lynx’s operating environment. In most
cases mid-scale is a good starting value.
7. Turn the stabilizer mode to On .
Since the stabilization algorithm relies on spectral data to establish its reference, and
changes in spectral data for its decisions on applying correction, the algorithm is
active when PHA acquire is On , and inactive when PHA acquire is Off . In addition,
once the stabilizer is activated, certain parameters that affect the signal storage cannot
be changed.