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Some isotopes undergo spontaneous fission (SF) with emission of neutrons.The most common spontaneous fission source is the isotope californium-252. 252 Cf and all other SF neutron sources are made by irradiating uranium or a transuranic element in a nuclear reactor, where neutrons are absorbed in the starting material and its subsequent reaction products, transmuting the starting material into ...
Californium-252 has a number of specialized uses as a strong neutron emitter; it produces 139 million neutrons per microgram per minute. [27] This property makes it useful as a startup neutron source for some nuclear reactors [ 17 ] and as a portable (non-reactor based) neutron source for neutron activation analysis to detect trace amounts of ...
Californium-252 (Cf-252, 252 Cf) undergoes spontaneous fission with a branching ratio of 3.09% and is used in small neutron sources. Fission neutrons have an energy range of 0 to 13 MeV with a mean value of 2.3 MeV and a most probable value of 1 MeV. [11] This isotope produces high neutron emissions and has a number of uses in industries such ...
Californium-252 from HFIR is used to treat brain and cervical cancers, to start up nuclear reactors, to help find belowground oil or gas and to detect hidden explosives and landmines.
A californium neutron flux multiplier (CFX) is a source of neutrons for research purposes. It contains a small amount of californium-252 and several plates of highly enriched uranium (uranium-235) in a subcritical configuration. As the californium undergoes spontaneous nuclear decay, it
ORNL sells milligrams of californium-252 to customers based on its value of $27 million per gram. A very strong neutron emitter, Cf-252 is used in portable metal detectors, for identifying gold ...
Generally the neutron source is a research reactor, [1] [2] where a large number of neutrons per unit area (flux) is available. Some work with isotope sources of neutrons has been completed (largely spontaneous fission of Californium-252, [3] but also Am-Be isotope sources, and others). These offer decreased capital costs and increased mobility ...
The primary sources are removed from the reactor after the first fuel campaign, usually after a few months, as neutron capture resulting from the thermal neutron flux in an operating reactor changes the composition of the isotopes used, reducing their useful lifetime as neutron sources. Californium-252 (spontaneous fission)