The muon g-2 experiment at Fermilab

W. Gohn

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arXiv · 1611.04964

The muon g-2 experiment at Fermilab

W. Gohn

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Abstract

A new measurement of the anomalous magnetic moment of the muon, $a_μ \equiv (g-2)/2$, will be performed at the Fermi National Accelerator Laboratory with data taking beginning in 2017. The most recent measurement, performed at Brookhaven National Laboratory and completed in 2001, shows a 3.5 standard deviation discrepancy with the standard model prediction of $a_μ$. The new measurement will accumulate 21 times those statistics using upgraded detection and storage ring systems, enabling a measurement of $a_μ$ to 140 ppb, a factor of 4 improvement in the uncertainty the previous measurement. This improvement in precision, combined with recent and ongoing improvements in the evaluation of the QCD contributions to the $a_μ$, could provide a 7.5$σ$ discrepancy from the standard model if the current difference between experiment and theory is confirmed, a possible indication of new physics.

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W. Gohn. 2016-11-15. The muon g-2 experiment at Fermilab. https://arxiv.org/abs/1611.04964

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