Page 18 - bukuneutron

1.4.2 Fission

Neutron resulting from fission process due to nuclear
reaction in the reactor fuel have a wide ranges of en-
ergy. It can be from cold neutrons up to fast neutrons
with energy 20 MeV, depending on the moderator and
core type used. Many research reactors presently are
developed with mainly for producing thermal neutron
and cold neutron.However, old research reactor mainly
for producing thermal neutron and used them in var-
ious fields of sciences and engineering applications.
Producing cold neutron required used of lithium or he-
lium liquid cooling system or solid beryllium inserted
in the reactor core. The applications of helium cooling
onto reactor core will produce mainly thermal and cold
neutron. While, the applications of water as the moder-
ator will produce neutron from thermal to fast neutron.

1.4.3 Spallation

Neutron is produced in spallation process when a heavy
ion or charge particle moving at high speed and col-
lided on the target materials, such as lead or deuterium.
The charged particle such as cation(+) or anion(-) can
be used as a heavy ion. The energy of heavy ion
should be higher than the potential energy between
nucleus and nucleon of the atom. One or more than
one neutron can be produced from one nucleus in the
spallation process. On the other hand, heavy ion should

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