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arXiv · 2512.20335

Status of the Muon g-2/EDM Experiment at J-PARC

Graziano Venanzoni
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Abstract

The Muon g-2/EDM Experiment at J-PARC will employ a novel way to measure the muon magnetic anomaly, a_mu = (g-2)_mu/2, by using a low-emittance beam of positive muons stored in a compact muon storage magnet. The experimental method includes new technologies such as a three-dimensional spiral injection, an MRI-type storage magnet with superb field uniformity, and a positron tracking detector. The expected systematic uncertainty will be at the same level as that of the Fermilab Muon g-2 experiment, providing an important cross-check of the "storage-ring method" employed at BNL and Fermilab. I will present the current status of the experiment, ongoing tests and design optimizations, and the plans for improvements of the experimental precision.

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Graziano Venanzoni. 2025-12-23. Status of the Muon g-2/EDM Experiment at J-PARC. https://arxiv.org/abs/2512.20335

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