Measurements of the electric and magnetic form factors of the proton from ${\mathit{Q}}^2$=1.75 to 8.83 (GeV/c${)}^2$

The proton elastic form factors ${\mathit{G}}_{\mathit{E}\mathit{p}}$(${\mathit{Q}}^2$) and ${\mathit{G}}_{\mathit{M}\mathit{p}}$(${\mathit{Q}}^2$) have been extracted for ${\mathit{Q}}^2$=1.75 to 8.83 (GeV/c${)}^2$ via a Rosenbluth separation to ep elastic cross section measurements in the angular range 13°≤θ≤90°. The ${\mathit{Q}}^2$ range covered more than doubles that of the existing data. For ${\mathit{Q}}^2$<4 (GeV/c${)}^2$, where the data overlap with previous measurements, the total uncertainties have been reduced to < 14% in ${\mathit{G}}_{\mathit{E}\mathit{p}}$ and < 1.5% in ${\mathit{G}}_{\mathit{M}\mathit{p}}$. Results for ${\mathit{G}}_{\mathit{E}\mathit{p}}$(${\mathit{Q}}^2$) are consistent with the dipole fit ${\mathit{G}}_{\mathit{D}}$(${\mathit{Q}}^2$)=(1+${\mathit{Q}}^2$/0.71${)}^{\mathrm{-}2}$, while those for ${\mathit{G}}_{\mathit{M}\mathit{p}}$(${\mathit{Q}}^2$)/${\mathrm{\mu }}_{\mathit{p}}$${\mathit{G}}_{\mathit{D}}$(${\mathit{Q}}^2$) decrease smoothly from 1.05 to 0.92. Deviations from form factor scaling are observed up to 20%. The ratio ${\mathit{Q}}^2$${\mathit{F}}_2$/${\mathit{F}}_1$ is observed to approach a constant value for ${\mathit{Q}}^2$>3 (GeV/c${)}^2$. Comparisons are made to vector meson dominance, dimensional scaling, QCD sum rule, diquark, and constituent quark models, none of which fully characterize all the new data.