Hardware Options
Lynx DSA User's Manual - 9240227J
109
Low-Energy Applications
For some low energy applications even the manual LLD cutoff may still prevent the
recording of very low energy events. For this purpose, in addition to the Manual LLD
Mode and LLD(%) setting, the Lynx exposes additional parameters in the Digital
Filter settings that extend the flexibility for low energy applications.
Low energy events can easily be captured by setting the
Slow Discriminator Mode
to
Manual
, and lowering the
Manual Slow Disc (%)
threshold towards 0.0% until
either the desired operation is achieved, or the noise level is reached.
Please note that with the Slow Discriminator Mode in Manual, excessively lowering
the
Manual Slow Disc (%)
setting will defeat noise discrimination, resulting in
excessive storage of noise events into the lower area of the spectrum and possibly
causing undesirable operation.
Stabilizer
The Spectrum Stabilizer applies only to PHA spectrums. The stabilizer algorithm in
the Lynx DSA is based on similar implementations of spectrum stabilization in other
CANBERRA MCA’s, where two user-defined regions of interest or windows are
used to monitor the count rate and control the stabilization.
The stabilizer algorithm periodically
monitors the count rate at the lower window
C
low
and the count rate at the upper window C
high
, then calculates the ratio between the two
as:
R
temp
= C
high
/C
low
R
temp
is then compared against a previously-established reference ratio R
ref
and if a
significant difference is found, a correction value is applied to the signal gain to
compensate for the drift.
