INTRODUCTION: The PUG-7N is a
complete fast-slow neutron monitor. It includes the PUG-7N, four-range
survey meter with attached detection system. Ranges are 0-500; 5,000;
50,000; and 500,000 cpm. Detection system includes PNS-20 plus moderator
with polyethylene inner sleeve and cadmium outer shield.
DESCRIPTION: The PUG-7N, or ``Neutron
PUG'' detects fast or slow neutrons by means of a thermal neutron
scintillation detector and a moderator. When the detector (Model #
PNS-20) is external to the moderator, thermal neutrons are detected
and measured by means of counts produced in the scintillator as read
on the meter of the PUG instrument.
The polyethylene moderator is surrounded by a cadmium
shield. The cadmium shield absorbs thermal neutrons and allows other
neutrons to enter the moderator. The moderator ``thermalizes''
the entering neutrons thus allowing them to affect the scintillator.
When the thermal neutron detector is within the moderator, thermal
neutrons are excluded by the cadmium layers and the detector measures
only fast neutrons which have entered the moderator and been ``thermalized''.
(See also the specification sheets on the PUG-7N survey meter and
Class: Portable - Survey meter used with
moderator and probe.
Principle of Operation: Boron - 10 in
ZnS (Ag) scintillator matrix (neutron, alpha reaction) and photomultiplier
tube, polyethylene moderator.
Epithermal to fast (Probe in moderator)
Thermal (Probe removed from moderator)
PNS-20 Probe Size: 2'' diameter x 8''
Moderator Size: Approximately 5'' diameter
x 6'' L
Weight: 8-3/4 pounds total weight
Shipping Weight: 15 pounds
Dimensions: 10-1/4'' L x 10'' H x 6''
W, including handle
Batteries: 2 each 9 Volt transistor battery,
Eveready # 1222 or equivalent