Status of the Muon g-2 Experiment at Fermilab

• Aaron Fienberg (University of Washington, Seattle)

Room: OSGA/E06 The E989 Muon g-2 Experiment at Fermilab aims to measure the anomalous magnetic moment of the muon, a_mu, to an unprecedented precision of 140 parts per billion (ppb), representing a four-fold improvement over the current best measurement achieved at Brookhaven National Lab. There stands a greater than 3 standard deviations discrepancy between the Brookhaven measurement of a_mu and the theoretical value predicted using the Standard Model. The Fermilab experiment seeks to either resolve or confirm this discrepancy, which is suggestive of new physics interactions. To achieve the E989 target precision, the anomalous precession frequency of muons in a magnetic storage ring must be determined with a systematic uncertainty below 70ppb, and the average magnetic field experienced by these stored muons must be known equally well. The muon anomalous precession frequency is imprinted on the time-dependent energy distribution of decay positrons observed by 24 electromagnetic calorimeters. A suite of pulsed NMR probes continually monitors the magnetic field. This talk will present the current status of the Fermilab experiment while emphasizing the ongoing analysis of the 2018 Run 1 dataset, roughly twice as large as the Brookhaven Experiment's, and the systematic effects that complicate it. Blinded analysis results demonstrating the mature state of the analysis and the quality of the collected data will be shown.