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The deuteron magnetic form factor B(${Q}^{2}$) has been measured at momentum transfers ${Q}^{2}$=1.21, 1.49, 1.61, 1.74, 1.98, 2.23, 2.48, 2.53, and 2.77 (GeV/c${)}^{2}$ at the Stanford Linear Accelerator Center by detection of electrons backscattered at 180\ifmmode^\circ\else\textdegree\fi{} in coincidence with recoiling deuterons at 0\ifmmode^\circ\else\textdegree\fi{}. The data for B(${Q}^{2}$) are found to decrease rapidly from ${Q}^{2}$=1.2 to 2 (GeV/c${)}^{2}$, then rise to a secondary maximum around ${Q}^{2}$=2.5 (GeV/c${)}^{2}$, in qualitative agreement with impulse-approximation calculations.

We report new results on a precision measurement of the ratio $R=\frac{{\ensuremath{\sigma}}_{L}}{{\ensuremath{\sigma}}_{T}}$ and the structure function ${F}_{2}$ for deep-inelastic electron-nucleon scattering in the kinematic range $0.2\ensuremath{\le}x\ensuremath{\le}0.5$ and $1\ensuremath{\le}{Q}^{2}\ensuremath{\le}10$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. Our results show, for the first time, a clear falloff of $R$ with increasing ${Q}^{2}$. Our $R$ and ${F}_{2}$ results are in good agreement with QCD predictions only when corrections for target-mass effects are included.

We measured the differences in R=σ_L/σ_T and the cross-section ratio σA/σD in deep-inelastic electron scattering from D, Fe, and Au nuclei in the kinematic range 0.2≤x≤0.5 and 1≤Q^2≤5 (Gev/c)^2. Our results for R^A-R^D are consistent with zero for all x and Q^2, indicating that possible contributions to R from nuclear higher-twist effects and spin-0 constituents in nuclei are not different from those in nucleons. The European Muon Collaboration effect is reconfirmed, and the low-x data from all recent experiments, at all Q^2, are now in agreement.

Cross sections for 180\ifmmode^\circ\else\textdegree\fi{} inelastic electron scattering from deuterium were measured from breakup threshold to beyond the quasielastic peak for incident-beam energies of 0.843, 1.020, 1.189, and 1.281 GeV, corresponding to $0.75\ensuremath{\le}{Q}^{2}\ensuremath{\le}2.57$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are in reasonable agreement with nonrelativistic models that include final-state interactions and meson-exchange currents. The scaling function $F(y)$ for these data is generally in agreement with $F(y)$ for forward-angle data at the same ${Q}^{2}$. Values of ${G}_{M}^{n}$ determined from the data are in good agreement with results from previous experiments.