Muon ( g − 2 )
نویسنده
چکیده
For a spin1 2 particle, ~ S = ~2~σ, and gs is called the Lande g-factor. From classical calculations that treat the charged particle as a rotating piece of current, gs = 1. Surprisingly, the Dirac equation in relativistic quantum mechanics predicts that gs = 2, a result which agreed with the crude experiments of the time. In the 1940’s, a new understanding of renormalization in the developing quantum field theory of electrodynamics allowed physicists like Feynman and Schwinger to make an unambiguous prediction that gs > 2 for the electron. This magnetic moment is noticeable when the particle is placed in an external field, because the Hamiltonian gains a term H = −~μ · ~ B. The spin will precess around the direction of the field with some frequency, and this is a way to measure the magnetic moment. Typically, we refer to the anomalous magnetic moment aμ instead of the full g-factor. For the muon:
منابع مشابه
Measurement of the Muon (g − 2)-value B. Lee Roberts on Behalf of the Muon (g − 2) Collaboration
The muon (g − 2) experiment is described, and the recent results are presented. These results represent the final measurement for the positive muon.
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The g-factor of the charged leptons has always been considered by many physicists, both experimentaly as well as theoretically. In fact the electron and muon g-factor play the main role in testing the QED as well as the standard model. Meanwhile, there is a discrepancy between the standard model prediction of the muon anomalies magnetic moment and its experimental determination as large as (25...
متن کاملar X iv : h ep - p h / 99 04 44 5 v 2 2 9 A pr 1 99 9 Muon g − 2 and New Physics
Here we invoke the current and future perspective on muon g −2 measurement when asking what the muon g − 2 could tell about the underlying structure concerning with the hierarchy problem. Here we take up two such models, the presence of which turns out to alter the standard model prediction for muon g − 2 significantly: one is TeV scale gravity scenario, the other supersymmetric model, in the l...
متن کاملar X iv : h ep - p h / 99 04 44 5 v 1 2 4 A pr 1 99 9 Muon g − 2 and New Physics
Here we invoke the current and future perspective on muon g −2 measurement when asking what the muon g − 2 could tell about the underlying structure concerning with the hierarchy problem. Here we take up two such models, the presence of which turns out to alter the standard model prediction for muon g − 2 significantly: one is TeV scale gravity scenario, the other supersymmetric model, in the l...
متن کاملar X iv : h ep - p h / 99 04 44 5 v 3 6 M ay 1 99 9 Muon g − 2 and New Physics
Here we invoke the current and future perspective on muon g −2 measurement when asking what the muon g − 2 could tell about the underlying structure concerning with the hierarchy problem. Here we take up two such models, the presence of which turns out to alter the standard model prediction for muon g − 2 significantly: one is TeV scale gravity scenario, the other supersymmetric model, in the l...
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We discuss a muon anomalous magnetic moment in a five dimensional SU(3) gaugeHiggs unification compactified on M × S/Z2 space-time including Z2-odd bulk mass for a fermion. We calculate one-loop corrections to the anomalous magnetic moment of muon and find a lower bound for the compactification scale to be around 5 ∼ 6 TeV by comparing nonzero Kaluza-Klein mode contributions with the muon (g − ...
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