Measurement of the Neutron Magnetic Form Factor

Abstract

The ratio of neutron and proton yields at quasifree kinematics was measured for the reactions ${}^{2}\mathrm{H}({e,e}^{\ensuremath{'}}n)$ and ${}^{2}\mathrm{H}({e,e}^{\ensuremath{'}}p)$ at momentum transfers ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.125$, 0.255, 0.417, and $0.605(\mathrm{GeV}/c{)}^{2}$, detecting the neutron and the proton simultaneously in the same scintillator array. The neutron detection efficiency was measured in situ with the ${}^{1}\mathrm{H}(\ensuremath{\gamma},{\ensuremath{\pi}}^{+})n$ reaction. From this the ratio $R$ of ${}^{2}\mathrm{H}({e,e}^{\ensuremath{'}}n)$ and ${}^{2}\mathrm{H}({e,e}^{\ensuremath{'}}p)$ cross sections was determined and used to extract the neutron magnetic form factor ${G}_{M}^{n}$ in a model insensitive approach, resulting in an inaccuracy between 2.1% and 3.3% in ${G}_{M}^{n}$.