Canberra 2015A, User Manual

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In the sample channel, the Model 2015A accepts the signal from the preamplifier,
shapes, delays and directs it through the SCA section for two simultaneous discrimina-
tions. In this application the proportional counter detector is biased to the beta plateau;
the output information from the detector is then indicative of both alpha and beta ener-
gies. Typically, the Single Channel Analyzer is set such that the SCA OUTPUT repre-
sents beta particles and the DISC (ULD) OUTPUT represents alpha particles. the
DISC (LLD) OUTPUT represents the sum of the alpha and beta particles.
The desired outputs from the single channel analyzer section are connected to the
Model 2209A AUTO FLOW METER and subsequent scalers. Figure 1 shows the
SCA and DISC information being routed by the 2209A to the respective scalers indi-
cating alpha and beta events. Both 2015A’s use the DISC output to provide ULD in-
formation. However, the WINDOW (
∆
E) control on the 2015A associated with the
cosmic channel is set to 0.00, thus its threshold is equal to that provided by the
LOWER LEVEL (E) control. The equipment setup is simplified since the 2015A in-
ternal controls are set the same. By utilizing the WINDOW (
∆
E) function, the cosmic
channel 2015A provides LLD information. The model 2015A’s included in this instru-
mentation makes the Alpha/Beta System a versatile, accurate, and cost effective sys-
tem.
3
Low Level
α/β
Counting System
Figure 1 Block Diagram of 2015A Application
in Low Level
α/β
Counting System