Model 44-157, 44-159, 44-159-1, 44-162
Gamma Pipe Monitors
Ludlum Measurements, Inc.
Page 1
September 2016
Introduction
The series of scintillator gamma pipe monitors (Models 44-157,
44-159, 44-159-1 and 44-162) is primarily used for detecting low
levels of gamma radiation in the range of 60 keV–1.25 MeV.
The Model 44-157 consists of a 2 x 2 inch NaI crystal coupled
to a photomultiplier tube housed in aluminum. The Model 44-
159 and 44-159-1 consist of an 18 x 18 mm CsI crystal, and the
Model 44-162, a 3 x 3 inch NaI crystal, both also coupled to a
photomultiplier tube housed in aluminum.
The detector is energy dependent, typically over-responding in
the 100 keV range and under-responding above 1 MeV when
normalized to
137
Cs.
The gamma pipe monitors will operate with any Ludlum
instruments or equivalent instruments that provide 700–1200
volts. The recommended instrument input sensitivity is
approximately 10 mV or higher.
Some common applications for this detector include
background radiation monitoring, low-level radiation detection,
and spectrum analysis when used in conjunction with a single-
or multi-channel analyzer.
Model 44-159-1
