Proton elastic form factor ratios to Q = 3.5 GeV2 by polarization transfer

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The ratio of the proton elastic electromagnetic form factors, GEp/GMp, was obtained by measuring Pt and P, the transverse and longitudinal recoil proton polarization components, respectively, for the elastic epepreaction in the four-momentum transfer squared range of 0.5 to 3.5 GeV2. In the single-photon exchange approximation, GEp/GMp is directly proportional to Pt/P. The simultaneous measurement of Pt and P in a polarimeter reduces systematic uncertainties. The results for GEp/GMp show a systematic decrease with increasing Q2, indicating for the first time a definite difference in the distribution of charge and magnetization in the proton. The data have been reanalyzed and their systematic uncertainties have become significantly smaller than those reported previously.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics
Original languageEnglish
Article number055202
JournalPhysical Review C: covering nuclear physics
Publication statusPublished - 2005
Publication categoryResearch

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