Final result at the Muon g-2 experiment at Fermilab

Abstract

The Muon g − 2 experiment at Fermilab’s goal was to determine the muon’s magnetic moment anomaly
with an unprecedented precision of 0.14 parts per million (ppm). The anomaly is extracted from the ratio
of the muon’s anomalous spin precession frequency in a magnetic storage ring to the magnetic field experienced
by the ensemble of muons. In this talk, I will present the analysis of data collected from 2020
to 2023, which has achieved a precision of 139 parts per billion (ppb) and, when combined with previous
results, leads to a new world average of 124 ppb [1]. I will show the result and discuss the experimental
technique, the analysis details and the control of systematic effects that were decisive in achieving the final
precision. This represents the most precise determination of the muon magnetic anomaly to date and
provides a critical benchmark for testing the Standard Model at the highest precision.