Ionization chamber for detecting neutrons:
Neutrons could also be detected through an ionization chamber. Since we already know, neutrons are uncharged; thus, they cause no ionizations themselves. The following reaction could take place if the inner surface of the ionization chamber is coated along with a thin coat of boron.
A neutron is captured through a boron atom and an energetic alpha particle is also emitted. An alpha particle causes ionization inside the chamber, and ejected electrons cause additionally secondary ionizations.
Another method for detecting neutrons by using an ionization chamber is to use the gas boron tri- fluoride (BF3) alters of air in the chamber. The incoming neutrons generate alpha particles while they react with the boron atoms in the detector gas. Either method might be used to detect neutrons within nuclear reactor neutron detectors.
While using an ionization chamber for detecting neutrons, beta particles could be avoided from entering the chamber through walls thick sufficient to shield out all of the beta particles. Gamma rays cannot be shielded from the detector; thus, they always contribute to the total current read through the ammeter. This effect is not desired since the detector responds not only to neutrons but also to gamma rays. Various ways are available to minimize this problem.