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arXiv · 2407.20375

The Proton Charge Radius from Dimuon Photoproduction off the Proton

Yong-Hui Lin·Feng-Kun Guo·Ulf-G. Meißner
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Abstract

We investigate the feasibility of measuring the proton charge radius through dimuon photoproduction off a proton target. Our findings indicate that the Bethe-Heitler mechanism, which dominates at small momentum transfers, allows for an extraction of the proton electromagnetic form factors in the extremely low $Q^2$ region below $10^{-3}$ GeV$^2$ in the spacelike region, when the incident photon beam energy exceeds several hundred MeV. The optimal kinematical region and a sensitivity study of the proton charge radius from dimuon photoproduction are presented. Such a measurement is expected to provide an alternative to the elastic muon-proton scattering measurements such as MUSE at PSI and AMBER at CERN.

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Yong-Hui Lin, Feng-Kun Guo, Ulf-G. Meißner. 2024-07-29. The Proton Charge Radius from Dimuon Photoproduction off the Proton. https://arxiv.org/abs/2407.20375

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