Question

Assume that a neutron that was just emitted as the result of a nuclear fission process in the core of a commercial Fukushima type boiling water reactor. Describe its initial state then describe at least five distinct and possible futures that could happen to the neutron after its emission.

Please include diagram if possible

Answer 1

The nuclear reactors is the efficient and clean way to produce electricity by boiling water using the heat produced by the fission reaction. In nuclear reactors, the nuclear fission reaction consist of a fission of uranium nuclei (generally U-235 or U-238 that break up and release neutrons along with heat energy in a conteneous process called chain reaction. There are two possible fission reactions of U-235 which releases average 2.4 neutrons per fission, which again strike other uranium atoms and triggers chain reaction. In order to control the chain reaction, moderator and water inseted among the tubes and the heat produced by the fission reaction absorbed by water.

There are several neutron released in chain reactions. Not all neutrons will be able to trigger chain reactions. Some of the neutrons undergoes eleastic and inealstic sacttering and some are lost through the radiative capture and undergoes lower energy neutron decay also beta-decay. The possible reactions are as follows,

  , Re-emitted electrons of low kinetic energy

, Emission of low energy neutron of low energy or beta-decay

Thus, before moderation in the nuclear reactor, neutrons emitted in the fission reactions undergoes (a) elastic scattering (b) inelastic scatterng, (c) radiative capture and emission of gamma rays, and (d) the neutron with sifficient kinetic energies trigers further fission reaction.

(e) After moderation, neutrons captured by moderator slowing down the encounter with Uranuim atoms.

(f) Also, there will be probality of neutron leacage in the reactor.