11
Neutrons, having no net charge, do not interact with matter
as easily as other particles, and can drift through great
thickness of material without incident. A free neutron, drift-
ing through space, will decay in an average of 11.7 min-
utes, yielding a proton and an electron (beta ray). The neu-
tron can also combine with the nucleus of an atom, if its
path carries it close enough. When a neutron is absorbed
into a nucleus, it is saved from its ultimate fate (decay), but
may render the nucleus unstable. This absorption process
is used in medicine and industry, to create radioactive ele-
ments from non-radioactive ones. Detecting neutrons is
specialized and beyond the scope of typical Geiger count-
ers, but most possible neutron sources also emit gamma
and beta radiation, affording detection of the source.
The highly energetic X-ray and gamma rays lose their en-
ergy as they penetrate matter. X-rays have an energy of up
to about 200,000 eV, compared to gamma radiation which
can be as energetic as several million eV. One million eV
gamma radiation can penetrate an inch of steel. Gamma
and X-ray radiation are by far the most penetrating of all
common types, and are only effectively absorbed by large
amounts of heavy, dense material of high atomic number,
such as lead.
SPECIFICATIONS
*(Cesium 137)
1mR/hr=10µS/hr
model
Calibration
Radiation
Range
Typical
Accuracy
Min/Max
Detection
Energy
840007
Gamma*
0~10 mR/hr
+20%
30 KeV ~
1.5 MeV
840026
Gamma*
0~100 mR/hr
+15%
30KeV ~
1.SMeV
