Determination of the neutron electric form factor in the $D(\vec{e},e^{\prime}\vec{n})p$ reaction and the influence of nuclear binding

The electric form factor of the neutron $G_{E,n}$ has been determined at the Mainz Microtron MAMI at the low momentum transfer $Q^{2}=0.15 \,{(GeV/c)}^{2}$ in a measurement of the recoil polarisation ratio $P_{x}/P_{z}$ in the quasifree reaction $D(\vec{e},e^{\prime}\vec{n})p$. At this $Q^{2}$ the influence of the nuclear binding is strong. A purely kinematical model is used to get some insight into the effect of the initial Fermi momentum distribution of the neutron. The influence of the final state interaction is determined quantitatively by a model of Arenhövel et al.. After the corresponding corrections a value of $G_{E,n}(0.15\,{(GeV/c)}^{2}) = 0.0481 \pm0.0065_{stat} \pm0.0053_{syst}$ is obtained