Page 19 - bukuneutron

be accelerated before bormbarding the target materi-
als. This bormbarding process is happened in a place
when properly shield.

1.5 Sources of Neutron

As mention earlier, the neutron can be produced in a
various way and environment. Several neutron sources
based on the way of neutrons are produced is dis-
cussed.

1.5.1 Sealed-Neutron Sources

Typical neutron sealed sources are Californium-252 (Cf-
252) and Americum-Berylium 241(AmBe-241) compos-
ite.The Cf-252 has emitted a spontaneous fast neutron
where AmBe-241 is producing neutrons when the α
particles collided on the beryllium target. The com-
posite of AmBe-241 or Cf-252 in the solid form and
each source is encapsulated within a stainless steel
capsule. A design of non-shielded cf-252 neutron is
given in Figure 1.3. Sealed source usually emitted a
wide spectrum of fast neutrons energy. Moderation of
fast neutron is required in order to obtain thermal neu-
tron. Materials rich with hydrogen such as high density
polyethylene or acrylic could be used as a moderator.

Therefore, neutron sealed source should be cou-
pled with a moderator and than shielded within a sand-

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