Proton Form Factors from Observation of Recoil Protons

A determination of the electric and magnetic form factors of the proton has been made by studying the elastic scattering of electrons from a polyethylene target by observation of the recoiling proton at 0° and 30° for values of $q^2$ between 1 and 1.8 ${\mathrm{F}}^{-2\mathrm{}}$. From these measurements we have deduced the charge radius $R_c$ and the magnetic radius $R_m$ of the proton and find equality within the experimental errors ($R_c=0.800\mathrm{}\pm 0.025$ F; $R_m=0.810\mathrm{}\pm 0.029$ F).