Canberra Lynx DSA, Руководство пользователя

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Acquisition Setup
Lynx DSA User's Manual - 9240227J 61
Integral, Area and Counts
Each of the three computational presets: Integral , Area , and Counts , applies to a
specified ROI.
To use any computational preset, you must specify its Value , the ROI's Start Channel
and its Stop Channel . The Start and Stop Channel values will default to the current
computational preset if there is one, otherwise the Start value will be 1 and the Stop
value will be the spectrum’s highest channel number.
ROI Selection
You can enter the Start Channel and Stop Channel limits manually or by using the
Current button in ROI Selection or the + and – buttons to move to the next ROI.
These functions automatically replace the limits with the current ROI’s start and stop
channels.
Note: ROI Start Channel and ROI Stop Channel values are with reference to the
PHA input size.
Coincidence
Coincidence is the ability to qualify the recording of incoming events. A qualifying
(gate) signal must arrive within a time window which is selectable by the user.
The gate input signal at the COINC/ANTI connector of the instrument's rear panel
determines which incoming signals are recorded. Events which do not meet the
qualification requirements are not recorded.
Mode (Gating)
Select the gating mode,
Coincidence
or
Anti-Coincidence
, or
Off
.
•
In
Off
, the coincidence logic is disabled; any signal at the COINC/ANTI
input will be ignored.
•
In
Coincidence
mode, an incoming pulse of the selected polarity within the
selected gate window permits recording of the event.
• In Anti- Coincidence mode, an incoming pulse of the selected polarity within
the selected gate window inhibits recording of the event.
Polarity
Selects the polarity of the gate input.
Positive
for active-high or
Negative
for active-
low input.
Gate Delay ( µ s)
Selects the time window (
µ
s) available for arrival of the qualifying gate pulse.
Recording of the event is delayed until the qualifying signal occurs or the window
time expires.