Low-Q2 measurements of the proton form factor ratio μpG E/GM

Physical Review C - PHYS REV C 03/2011; 84(05). DOI: 10.1103/PhysRevC.84.055204
Source: arXiv


We present an updated extraction of the proton electromagnetic form factor
ratio, mu_p G_E/G_M, at low Q^2. The form factors are sensitive to the spatial
distribution of the proton, and precise measurements can be used to constrain
models of the proton. An improved selection of the elastic events and reduced
background contributions yielded a small systematic reduction in the ratio mu_p
G_E/G_M compared to the original analysis.

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