Muon g-2 measurement

Helpful diagrams to explain the measurement of the anomalous moment g-2 of the muon, via its precession in the magnetic field of a storage ring at FNAL.
Also see general magnetic moment diagrams, or the “decay” tag for more similar figures.

Uniform circular motion of a positively charged particle in a uniform magnetic field with cyclotron frequency ω_C:

Uniform circular motion of a negatively charged particle:

Muon spin and momentum are aligned at all times in the storage ring if g = 2 exactly.

If g > 2, the muon spin will rotate faster due to anomalous precession.

Anomalous frequency ω_a with some initial phase shift:

Edit and compile if you like:

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% Author: Izaak Neutelings (March 2020)
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