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for this interaction, and are routinely measured experimentally; these three effective vertices can then be used to check, or perform calculations that would otherwise be too difficult to perform from first principles. This matrix element then serves to determine the transition amplitude involved in
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241:{\displaystyle \varepsilon _{\mu }{\bar {N}}\left(\alpha (q^{2})\gamma ^{\mu }+\beta (q^{2})q^{\mu }+\kappa (q^{2})\sigma ^{\mu \nu }q_{\nu }\right)N\,}
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Perdrisat and Vina Punjabi (2010). "Nucleon Form factors",
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the scattering interaction or the respective particle decay—cf.
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Wilson, R. (1969). "Form factors of elementary particles",
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468:Elementary Particle Physics
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399:Photon structure function
271:{\displaystyle q^{\mu }}
282:(equal in magnitude to
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55:Photon–nucleon example
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591:Quantum physics stubs
332:magnetic form factors
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464:Gasiorowicz, Stephen
441:Quantum Field Theory
404:Quantum field theory
394:Magnetic form factor
389:Electric form factor
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41:particle interaction
25:mathematical physics
357:are a probe of the
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337:Fermi's golden rule
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379:Structure function
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314:κ
308:β
302:α
264:μ
225:ν
215:ν
212:μ
208:σ
188:κ
180:μ
156:β
148:μ
144:γ
124:α
113:¯
102:μ
98:ε
466:(1966),
439:(1994).
373:See also
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328:electric
290:, where
280:momentum
37:function
65:nucleon
63:with a
45:physics
492:p 47,
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251:where
73:gluons
69:quarks
61:photon
531:This
459:p 400
363:gluon
359:quark
35:is a
537:stub
472:ISBN
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361:and
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23:and
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352:QCD
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110:N
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