Description:

Abstract: The muon is a heavy cousin of the ordinary electron and like electrons the muon's magnetic.  It's magnetic moment, or so-called g-factor, is a well-known test of the standard model and a unique probe of the virtual-particle zoo of the quantum-mechanical vacuum. Twenty years ago, the Brookhaven g-2 experiment measured the muon anomaly aµ = (g-2)/2 to 540 ppb and found a 2.5 standard deviation discrepancy with the standard model prediction.

The tantalizing BNL result became the driving force for both a new Fermilab Muon g-2 experiment and the international Muon g-2 Theory Initiative.  In this colloquium I'll present an overview of the physics of the muon's g-factor and the basic methods and the first results from the Fermilab Muon g-2 experiment. The combination of earlier 540 ppb BNL result and our run 1, 460 ppb result indicates a 4.2 standard deviation discrepancy with the Theory Initiative's Standard Model consensus value for aµ.

The Fermilab experiment is continuing to collect data. We now have acquired roughly 10 times the BNL dataset and plan to acquire roughly 20 times the BNL dataset to reach the goal of a 120 ppb, aµ measurement.

Seminar Speaker: Professor Tim Gorringe, University of Kentucky

Host: John Joseph Carrasco

Meeting Details:
Friday, May 21, 2021 at 4:00 pm (Central Time) on Zoom.

Zoom info:
Please email samantha.westlake@northwestern.edu if you would like access to the Zoom meeting link.