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Measurement of the muon anomaly to high and even higher precision

David W. Hertzog
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Abstract

Our recent series of measurements at Brookhaven National Laboratory determined the muon anomalous magnetic moment \amu to a precision of 0.5 ppm. The final result--representing the average of five running periods using both positive and negative muons--is $\amu ^\pm = 11 659 208(6) \times 10^{-10}$. It lies 2.7 standard deviations above the standard model expectation, which is based on updates given at this Workshop. Importantly, only the $e^{+}e^{-}$ annihilation and new KLOE radiative return data are used for the hadronic vacuum polarization input. Because the systematic limit has not been reached in the experiment, a new effort has been proposed and approved with the highest scientific priority at Brookhaven. The goal is an experimental uncertainty of 0.2 ppm, a 2.5-fold reduction in the overall experimental uncertainty. To do so will require a suite of upgrades and several qualitative changes in the philosophy of how the measurement is carried out. I discuss the old and new experiments with a particular emphasis on the technical matters that require change for the future.

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David W. Hertzog. 2005-01-20. Measurement of the muon anomaly to high and even higher precision. https://doi.org/10.1016/j.nuclphysbps.2005.02.027

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