Low-${Q}^{2}$ measurements of the proton form factor ratio ${\ensuremath{\mu}}_{p}{G}_{E}/{G}_{M}$

Low- $Q^{2}$ measurements of the proton form factor ratio $μ_{p} G_{E} / G_{M}$

G. Ron et al. (The Jefferson Lab Hall A Collaboration)

Phys. Rev. C 84, 055204 – Published 21 November 2011

Abstract

We present an updated extraction of the proton electromagnetic form factor ratio, $μ_{p} G_{E} / G_{M}$ , 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 $μ_{p} G_{E} / G_{M}$ compared to the original analysis.