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arXiv · 1001.3341

Precision Measurements of the Proton Elastic Form Factor Ratio

Abstract

New high precision polarization measurements of the proton elastic form factor ratio in the Q^2 range from 0.3 to 0.7 [GeV/c]^2 have been made. These elastic H(e,e'p) measurements were done in Jefferson Lab's Hall A using 80% longitudinally polarized electrons and recoil polarimetry. For Q^2 greater than 1 [GeV/c]^2, previous polarization data indicated a strong deviation of the form factor ratio from unity which sparked renewed theoretical and experimental interest in how two-photon diagrams have been taken into account. The new high precision data indicate that the deviation from unity, while small, persists even at Q^2 less than 1 [GeV/c]^2.

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D. W. Higinbotham. 2010-01-23. Precision Measurements of the Proton Elastic Form Factor Ratio. https://doi.org/10.1063/1.3483410

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