ORTEC 572A, Руководство по эксплуатации и обслуживанию

Страница: 22 / 30

16
Fig. 4.11. System for High-Resolution Alpha-Particle Spectroscopy.
Fig. 4.12. System for High-Resolution Gamma
Spectroscopy.
SCINTILLATION-COUNTER GAMMA
SPECTROSCOPY SYSTEMS
The ORTEC 572A
can be used in scintillation-counter spectroscopy
systems as shown in Fig. 4.13. The amplifier
shaping time constants should be selected in the
region of 0.5 to 1 µs for NaI or plastic scintillators.
For scintillators having longer decay times, longer
time constants should be selected.
X - R A Y S P E C T R O S C O P Y U S I N G
PROPORTIONAL COUNTERS
Space charge
effects in proportional counters, operated at high
gas amplification, tend to degrade the resolution
capabilities drastically at x-ray energies, even at
relatively low counting rates. By using a high-gain
low-noise amplifying system and lower gas
amplification, these effects can be reduced and a
considerable improvement in resolution can be
obtained. The block diagram in Fig. 4.14 shows a
system of this type. Analysis can be accomplished
by simultaneous acquisition of all data on a
multichannel analyzer or counting a region of
interest in a single-channel analyzer window with a
counter and timer or counting ratemeter.
4.10. OTHER EXPERIMENTS
Block diagrams illustrating how the 572A and other
ORTEC modules can be used for experimental
setups for various other applications are shown in
Figs. 4.15 through 4.18.