The fixed probe storage ring magnetometer for the Muon g-2 experiment at Fermi National Accelerator Laboratory
Abstract
The goal of the FNAL E989 experiment is to measure the muon magnetic anomaly to unprecedented accuracy and precision at the Fermi National Accelerator Laboratory. To meet this goal, the time and space averaged magnetic environment in the muon storage volume must be known to better than 70 ppb. A new pulsed proton nuclear magnetic resonance (NMR) magnetometer was designed and built at the University of Washington, Seattle to track the temporal stability of the 1.45T magnetic field in the muon storage ring at this precision. It consists of an array of 378 petroleum jelly based NMR probes that are embedded in the walls of muon storage ring vacuum chambers and custom electronics built with readily available modular radio frequency (RF) components. We give NMR probe construction details and describe the functions of the custom electronic subsystems. The excellent performance metrics of the magnetometer are discussed, where after 8 years of operation the median single shot resolution of the array of probes remains at 650 ppb.
Keywords
Cite
@article{arxiv.2410.08279,
title = {The fixed probe storage ring magnetometer for the Muon g-2 experiment at Fermi National Accelerator Laboratory},
author = {Erik Swanson and Martin Fertl and Alejandro Garcia and Cole Helling and Ronaldo Ortez and Rachel Osofsky and David A. Peterson and Rene Reimann and Matthias W. Smith and Tim D. Van Wechel},
journal= {arXiv preprint arXiv:2410.08279},
year = {2025}
}
Comments
19 pages, 20 figures