Fermi constant

E88966

The Fermi constant is a fundamental physical constant that quantifies the strength of the weak nuclear force in processes such as beta decay.


Statements (48)
Predicate Object
instanceOf fundamental constant
physical constant
weak interaction constant
alsoKnownAs Fermi coupling constant
Fermi weak coupling constant
appearsIn Fermi’s beta decay Hamiltonian
low-energy effective weak interaction Lagrangian
weak charged-current interactions
definedInContextOf four-fermion contact interaction
describes strength of the weak nuclear force
determinedFrom muon lifetime measurements
energyScaleImplication corresponds to weak scale around 300 GeV
fieldOfStudy electroweak interaction
nuclear physics
particle physics
governs rate of beta decay
rate of muon decay
hasApproximateValue 1.1663787×10^{-5} GeV^{-2}
hasApproximateValueUncertainty 6×10^{-12} GeV^{-2}
hasCODATAValueYear 2018
hasDimension (energy)^{-2}
(mass)^{-2}
hasPhysicalMeaning probability amplitude per unit time and volume for weak processes
hasSIUnit GeV^{-2}
J^{-2}·m^{3}·s^{-1}
inNaturalUnits G_F ≈ 1.166×10^{-5} GeV^{-2}
introducedBy Enrico Fermi
is effective coupling constant at low energies for weak interaction
isLowEnergyLimitOf W boson exchange interaction
isPositive true
relatedConstant Planck constant
elementary charge
fine-structure constant
speed of light
relatedTo Higgs vacuum expectation value
W boson mass
beta decay
four-fermion interaction
weak interaction
weak mixing angle
roleInStandardModel sets overall scale of weak interaction strength
symbol G_F
usedAsInputParameterIn precision electroweak fits
usedIn Fermi theory of beta decay
Standard Model of particle physics
calculation of weak interaction cross sections
electroweak theory
muon decay rate calculations

Referenced by (4)
Subject (surface form when different) Predicate
Fermi constant ("Fermi weak coupling constant")
alsoKnownAs
Enrico Fermi
hasEponym
Fermi theory of beta decay ("Fermi coupling constant")
introducesConcept
Fermi theory of beta decay
relatedTo

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