Model 42-49 Neutron Detector
Technical Manual
Section 3
Ludlum Measurements, Inc.
Page 3-1
December 2017
Specifications
0
Detector:
2 atm ³He tube LND 25185 or equivalent
Moderator:
19.6 cm (7.7 in.) diameter high density polyethylene sphere
Compatible Instruments:
typically used with portable counting
instruments (capable of achieving -2 mV input sensitivity)
Sensitivity:
100 cpm/mrem/hr (
241
AmBe fast neutrons)
Gamma Rejection:
10 cpm or less through 10 R/hr (100 mSv/hr) (
137
Cs)
Detection Range:
thermal to approximately 12 MeV
Energy Response:
thermal to 12 MeV, follows the radiation protection
guide curve for neutron dose
Input Sensitivity:
-2 mV
Operating Voltage:
approximately 1200 V
Connector:
series “C” (others available)
Temperature Range:
-20 to 50 °C (-4 to 122
°
F)
Size:
25.5 x 19.6 x 19.6 cm (10 x 7.7 x 7.7 in.) (H x W x D), including
brackets
Weight:
4.6 kg (10.2 lb)
Section
3