Experiences from the Commissioning and First Physics Run of the Fermilab Muon g-2 Experiment

TL;DR

The Fermilab Muon g-2 experiment aims to precisely measure the muon's anomalous magnetic moment to resolve existing discrepancies with the Standard Model, with recent commissioning and initial physics results demonstrating significant progress.

Contribution

This paper reports on the improvements and initial results from the Fermilab Muon g-2 experiment's commissioning and first physics run, advancing the precision measurement of $a_{}$.

Findings

Successful commissioning of the experiment setup.

Initial measurement of the muon anomalous magnetic moment.

Progress towards achieving the target precision of 140 ppb.

Abstract

The Muon g-2 Experiment (E989) at Fermilab is seeking to measure the anomalous magnetic moment of muon ($a_{\mu}$) with a precision of 140 parts-per-billion (ppb) and aiming to resolve the discrepancy between the E821 measurement and the Standard Model calculation of $a_{\mu}$. In E989, the muon beam is stored in a ring magnet. The anomalous spin precession frequency $\omega_{a}$ is measured by counting decay positrons in 24 calorimeters, and the magnetic field is measured by nuclear magnetic resonance (NMR) probes. Improvements in this experiment with respect to its predecessor and the progress achieved in the commissioning run and the first physics run, Run-1, are presented.