Ludlum Measurements 43-147, Руководство пользователя

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Models 43-147 Technical Manual
Section 1
Ludlum Measurements, Inc. Page 1-1 March 2019
Introduction
he Model 43-147 detector is designed for alpha-beta surveying when
coupled with compatible instruments. Functionally, these two
detectors are very similar but differ in the type of protective window
screen and the size of the active and open window areas.
Discriminating between alpha and beta radiation simultaneously requires the
counting instrument to have either separate power supplies or
window/threshold controls for each channel. The Ludlum Model 2929 Scaler,
Model 2223, Model 2224, or Model 2360 instruments provide the necessary
circuitry for simultaneous alpha-beta discrimination.
A Zinc Sulfide [ZnS (Ag)] scintillator is used for detecting alpha particles, and a
thin plastic scintillator is employed for detecting beta radiation. The scintillation
material is covered by metallized polyester to reduce light response, limiting
excessive background counts. The Model 43-147 window is protected by an
88% open square-hole screen.
The photomultiplier tube (PMT) and crystal assembly may easily be removed
for repair. Refer to the assembly view drawing in section 5 of this manual for
details on construction and parts. The photomultiplier tube typically operates
between 500 and 1200 volts with a recommended maximum of 1500 volts.
Section
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