Measurement of elastic electron-neutron scattering and inelastic electron-deuteron scattering cross sections at high momentum transfer

We have measured inelastic electron-deuteron, electron-proton, and electron-aluminum cross sections at 10° in the kinematic region between elastic deuteron scattering and the second resonance region at six beam energies between 9.8 and 21 GeV. The elastic electron-neutron cross section was extracted from the quasielastic data at $Q^2=2.5,4.0,6.0,8.0, \mathrm{and} 10.0$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$. The ratio of elastic cross sections $\frac{{\sigma }_n}{{\sigma }_p}$ falls with increasing $Q^2$ above 6 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$. The inelastic data are compatible either with $y$ scaling (scattering from a single nucleon) or with $\xi$ scaling (scattering from quarks).