Muon’s Escalating Challenge to the Standard Model
April 7, 2021•
Physics 14, 54
Measurements of the muon magnetic moment strengthen a previously reported tension with theoretical predictions, ushering in a new era of precision tests of the standard model.
Reidar Hahn/Fermilab
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2 ring, where the precession of muons in a magnetic field is used to measure the muon magnetic moment.
Reidar Hahn/Fermilab
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2 ring, where the precession of muons in a magnetic field is used to measure the muon magnetic moment.×
Twenty years ago, the Brookhaven Muon
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2 experiment measured a value of the anomalous magnetic moment of the muon that disagreed by several parts per million with calculations based on the standard model (SM) of particle physics [1]. Physicists had long understood that the SM was incomplete, but the Muon