Ludlum Measurements 43-147, Manual

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Models 43-147 Technical Manual
Section 2
Ludlum Measurements, Inc. Page 2-1 March 2019
Specifications
0
Photomultiplier Tube
: 2.9 cm (1.1 in.) diameter; magnetically shielded
Scintillator Material
: Zinc Sulfide [ZnS (Ag)] deposited on a 0.25 mm
(0.010 in.) rectangular plastic scintillator
Removable Protective Screen:
0.79 mm (0.03 in.) thick, 6.5 mm (0.26
in.) square openings, 88% open
Screen Outer Dimensions:
225.4 x 113.7 mm (8.875 x 4.75 in.) (L x W)
Window
: 1.2 mg/cm
2
metalized polyetser
Window Area:
Active area
: approximately 200 cm
2
Open area
: approximately 176 cm
2
Efficiency (4  )
: typically 13% for
99
Tc, 20% for
90
Sr
90
Y, and 20% for
239
Pu
Background
(in a 10
µ
R/hr field):
Alpha: 3 cpm or less
Beta: 400 cpm or less
Cross Talk:
Alpha to Beta: < 10%
Beta to Alpha: < 1%
Response Uniformity
: 10% or less from average reading
Operating Voltage
: typically 500-1200 Vdc (1500 Vdc max.)
Section
2