The glossary story... Home    Author    Research    Methodology    Contact
  Glossary terms... A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    XYZ    numbers
  Collections... dose    elements    neutrons    nuclides    radiation    radioactive decay    reactions    reactors radiation safety   
units    U.S.Regs   
  Further Reading... general    nuclear science    nuclear engineering    health physics   
A symbol for fluorine.

An acronym for fuel assembly.

A synonym for decay chain.

fast fission
Fission induced by fast neutrons.

Related to fast neutron.

fast neutron
(1) A neutron with an energy considerably greater than thermal energies, sometimes defined as having an energy greater than 1 eV and sometimes defined as having an energy of greater than 100 keV.

(2) A prompt or delayed neutron produced in fission that has not lost appreciable energy.

Related to cold neutron.
Related to continuum region neutron.
Related to epithermal neutron.
Related to low energy region neutron.
Related to resonance region neutron.
Related to slow neutron.
Related to thermal neutron.
Related to ultra cold neutron.
Related to very cold neutron.

fast reactor
A nuclear reactor in which the fission chain reaction is sustained primarily by fast neutrons.

An acronym for fuel cycle.

An acronym for feedwater.

A symbol iron.

For gaseous isotope diffusion it is the material that enters the cascade.

Related to product.
Related to waste.

Water used to remove heat from a reactor and produce steam to drive the turbine generators. This water is supplied directly to the reactor pressure vessel in a boiling water reactor. It is supplied to the steam generator in a pressurized water reactor.

Acronym: FW.
Acronym: FDW.

A chemical element with atomic number 100. Fermium was reported to have been discovered in 1952 when Albert Ghiorso, Glenn Seaborg, and associates at the University of California Radiation Laboratory, Argonne National Laboratory, and Los Alamos National Laboratory were testing debris of a thermonuclear explosion in the South Pacific during the same year. Fermium was actually discovered some time during World War II but its announcement was delayed because of security concerns. The name fermium was given in honor of Enrico Fermi.

Symbol: Fm.
Related to actinides.

Nuclides that can produce fissile nuclides under neutron irradiation. Fertile nuclides generally themselves do not undergo induced fission. The nuclide 238U is an example. While this nuclide does not itself undergo induced fission, capture of a neutron by 238U produces 239U which then β- decays to 239Pu, a nuclide with a large neutron-induced fission cross section.

fertile material
Material that contains fertile nuclides.

Related to fertile nuclide.
Related to fissile material.

fertile nuclide
A nuclide that can be converted into a fissile nuclide through neutron capture.

Related to fertile material.
Related to fissile material.

An acronym for fission gases.

film badge
A small badge containing photographic film that is worn by personnel to monitor radiation exposure. Gamma rays and beta particles that interact with the film cause a darkening whose intensity is a function of dose.

Related to dose.
Related to film ring.

film ring
Related to film badge.

A nuclide capable of undergoing neutron-induced fission. The nuclides 235U and 239Pu are classified as fissile because they have very large cross sections for neutron-induced fission.

fissile material
Materials that contain 238Pu, 239Pu, 241Pu, 233U, 235U, or any combination of these nuclides. Unirradiated natural uranium and depleted uranium, and natural uranium or depleted uranium that have only been irradiated in thermal reactors are not included in this definition. Certain exclusions from fissile material controls are provided in 10CFR part 71.53.

Reference: 10CFR71.
Related to fertile material.
Related to fertile nuclide.

fissile material package
Fissile material packaging together with its fissile material contents.

Reference: 10CFR71.
Related to package.
Related to type B package.

The process of splitting a heavy nucleus into two lighter nuclei. Spontaneous fission is a type of radioactive decay for some nuclides, such as 252Cf. In other nuclides fission is induced through the reaction of an incident radiation with the nucleus. Neutron-induced fission of 235U is a common example. Considerable energy is released during the fission reaction and this energy can be used to produce heat and electricity.

Synonym: atomic fission.
Synonym: nuclear fission.
Related to fission fragment.
Related to fission neutron.
Related to fission product.
Related to neutron chain reaction.
Related to neutron generation.
Related to nuclear fusion.
Related to photofission.
Related to spontaneous fission.
Related to ternary fission.

Capable of undergoing spontaneous fission or induced fission.

fissionable material
Fissile material. Can also include material that can be fissioned by fast neutrons.

fission cross section
The probability a reaction will occur that will cause a nuclide to fission.

Symbol: σf.
Related to barn.
Related to capture cross section.
Related to cross section.
Related to scattering cross section.

fission fragment
A nucleus formed as a direct result of fission. Fission products formed by the decay of these nuclides are not included.

Synonym: primary fission product.
Synonym: fission recoil.
Related to fission.
Related to fission product.
Related to photofission.
Related to spontaneous fission.
Related to ternary fission.

fission gases
Fission products that exist in the gaseous state. Krypton and Xenon are the dominant fission gases.

fission neutron
A neutron emitted as a nuclide undergoes fission.

Related to delayed fission neutron.
Related to fission.
Related to fission product.
Related to photofission.
Related to prompt fission neutron.
Related to spontaneous fission.
Related to ternary fission.

fission poison
Materials with ultra-high neutron capture cross sections that significantly reduce neutron fields in a reactor, reducing reactivity, thereby creating a barrier to reactor operations. The nuclides 149Sm and 135Xe are two poisons that are produced as fission products with a high yield and which have an impact on reactor operations.

Synonym: neutron poison.
Synonym: poison.

fission product
A residual nucleus formed in fission, including fission fragments and their decay daughters.

Acronym: FP.
Related to fission.
Related to photofission.
Related to spontaneous fission.
Related to ternary fission.

fission recoil
A synonym for fission fragment.

The number of particles per unit area. It is a time-integrated flux.

A chemical element with atomic number 9. Fluorine was discovered by Scheele in 1771, and was isolated by Henri Moissan in 1866 when he electrolyzed potassium hydrogen fluoride with hydrochloric acid. The name fluorine is derived from fluere, French for flow.

Symbol: F.
Related to halogens.

The number of particles per unit area per unit time.

A symbol fermium.

formula quantity
Strategic special nuclear material in any combination in a quantity of 5000 grams or more. It is computed by the following formula: masstotal = massU-235 + 2.5 × (massU-233 + massPu).

References: 10CFR70, 10CFR73, 10CFR74, 10CFR76.
Synonym: category I quantity.

fossil fuel
Ancient deposits of coal or oil used as a source of fuel for transportation, heating, or production of electricity.

An acronym for fission product.

A symbol francium.

A chemical element with atomic number 87. Francium was discovered in 1939 by Marguerite Perey, a student at the Curie Institute in Paris, who was conducting experiments on actinium. The name francium was given in honor of France. The only isotope of francium that occurs in nature is 223Fr, a member of the actinium decay chain.

Symbol: Fr.
Related to alkali metals.

free annihilation
Annihilation of an antiparticle that occurs without the formation of an atom-like structure with its corresponding particle. For the positron, it is annihilation without the formation of the positronium.

Related to annihilation.
Related to pick-off annihilation.
Related to singlet state annihilation.
Related to triplet state annihilation.

A synonym for nuclear fuel.

fuel assembly
A synonym for fuel element.

Acronym: F/A.
Acronym: FFA.

fuel cladding
Material used to construct reactor components and designed to maintain a separation between their contents and the coolant. An example is the cladding of a fuel pin that separates the fuel pellets from the coolant. Zirconium and zirconium alloys (e.g., Zircaloy) are common cladding materials.

Synonym: cladding.

fuel cycle
All steps in the use of fissile material as fuel for a reactor, including mining, purification, isotopic enrichment, fuel fabrication, irradiation, storage of irradiated fuel, reprocessing and disposal.

Acronym: FC.

fuel element
A cluster of fuel pins mounted into a single assembly.

Synonym: fuel assembly.
Synonym: fuel rod.
Related to fuel pellet.
Related to fuel pin.

fuel pellet
A small cylinder of enriched uranium, typically as UO2. Several fuel pellets are assembled into a fuel pin which forms a component of a fuel element.

Synonym: pellet.
Related to fuel element.
Related to fuel pin.

fuel pin
A long slender tube made of a zirconium alloy and containing fuel pellets. Several fuel pins are bundled together to form a fuel element.

Related to fuel element.
Related to fuel pellet.

fuel reprocessing
A synonym for reprocessing.

fuel rod
A synonym for fuel element.

Synonym for nuclear fusion.

An acronym for feedwater.
Copyright © 2003-2006 Scientific Digital Visions, Inc. All rights reserved.

Our partner sites:
Argus Clearinghouse 
Qualitatively bus charters to get a camera