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Individual low-energy $E1$ toroidal and compressional states (TS and CS) produced by the convective nuclear current ${\mathbf{j}}_{c}$ were recently predicted for $^{24}\mathrm{Mg}$ in the framework of quasiparticle random-phase approximation (QRPA) with Skyrme forces. In the present QRPA study with Skyrme parametrization SLy6, we explore in more detail properties of these states [toroidal and compressional responses, current distributions, and transitions probabilities $B(E1K,{0}^{+}0\ensuremath{\rightarrow}{1}^{\ensuremath{-}}K),\phantom{\rule{0.28em}{0ex}}B(E3K,{0}^{+}0\ensuremath{\rightarrow}{3}^{\ensuremath{-}}K)$, and $B(M2K,{0}^{+}0\ensuremath{\rightarrow}{2}^{\ensuremath{-}}K)$ with $K=0$ and 1] and analyze the possibility to discriminate and identify TS in inelastic electron scattering to back angles. The interplay of the convective ${\mathbf{j}}_{c}$ and magnetization ${\mathbf{j}}_{m}$ nuclear currents is thoroughly scrutinized. A two-step scheme for identification of TS in $(e,{e}^{\ensuremath{'}})$ reaction is proposed. The key element of the scheme is the strong interference of the orbital and spin contributions, resulting in specific features of $E1$ and $M2$ transversal form factors.

We measured the ${}^{12}\mathrm{C}{(e,e}^{\ensuremath{'}}p)$ cross section as a function of missing energy in parallel kinematics for $(q,\ensuremath{\omega})=(970 \mathrm{MeV}/c, 330 \mathrm{MeV})$ and $(990 \mathrm{MeV}/c, 475 \mathrm{MeV}).$ At $\ensuremath{\omega}=475 \mathrm{MeV},$ at the maximum of the quasielastic peak, there is a large continuum ${(E}_{m}g50 \mathrm{MeV})$ cross section extending out to the deepest missing energy measured, amounting to almost 50% of the measured cross section. The ratio of data to distorted-wave impulse approximation (DWIA) calculation is 0.4 for both p and s shells. At $\ensuremath{\omega}=330 \mathrm{MeV},$ well below the maximum of the quasielastic peak, the continuum cross section is much smaller and the ratio of data to DWIA calculation is 0.85 for the p shell and 1.0 for the s shell. We infer that one or more mechanisms that increase with $\ensuremath{\omega}$ transform some of the single-nucleon knockouts into a multinucleon knockout, decreasing the valence knockout cross section and increasing the continuum cross section.

Discrete states in $^{18}\mathrm{O}$ up to 25 MeV of excitation were studied by inelastic electron scattering. The measurements were performed at the Bates Linear Accelrator Center at 110\ifmmode^\circ\else\textdegree\fi{} and 140\ifmmode^\circ\else\textdegree\fi{}, and at momentum transfers ranging from about 1.2 to 2.5 ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}$. A number of the states discussed here have not been observed previously. Form-factor measuremetns are presented for eight ${4}^{\mathrm{\ensuremath{-}}}$ candidates and for two ${6}^{\mathrm{\ensuremath{-}}}$ candidates. The strongest ${4}^{\mathrm{\ensuremath{-}}}$ state has T=2 and was observed at 22.40 MeV. Good T=2 ${4}^{\mathrm{\ensuremath{-}}}$ candidates were found at 18.68 and 20.36 MeV, and good T=1 ${4}^{\mathrm{\ensuremath{-}}}$ candidates were found at 8.52 and 12.99 MeV; the strongest ${6}^{\mathrm{\ensuremath{-}}}$ candidate was found at 14.17 MeV. Form-factor measurements are also presented for several ${2}^{\mathrm{\ensuremath{-}}}$ candidates. The M2 form factor for the lowest ${2}^{\mathrm{\ensuremath{-}}}$ state at 5.53 MeV is similar in shape to that for the lowest ${2}^{\mathrm{\ensuremath{-}}}$ state in $^{16}\mathrm{O}$, but is weaker in strength. Finally, form-factor measurements are presented for several high-lying normal-parity states, including strong excitations at 9.36, 9.71, 11.67, and 17.02 MeV.

Low-multipolarity magnetic transitions of $^{30}\mathrm{Si}$, $^{32}\mathrm{S}$, and $^{34}\mathrm{S}$ were studied by 180\ifmmode^\circ\else\textdegree\fi{} inelastic electron scattering at low momentum transfers (q\ensuremath{\sim}0.3\char21{}0.5 ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}$). These measurements, made in the excitation energy region from 9 to 14 MeV, revealed several previous unreported levels. These are the first low-q results obtained by electron scattering for $^{30}\mathrm{Si}$ and $^{34}\mathrm{S}$. Multipolarities and transition strengths for all the observed transitions were determined in a model-independent analysis. A large fragmentation of M1 strength is observed in the 4N+2 nuclei $^{30}\mathrm{Si}$ and $^{34}\mathrm{S}$, while more strength is concentrated into fewer transitions in the self-conjugate nucleus $^{32}\mathrm{S}$. The experimental M1 strength distributions are compared with configuration-mixing shell-model calculations. The sums of the transition strengths are in good agreement with recent shell-model calculations using an effective M1 operator.

Measurements of inelastic electron scattering from {sup 36}Ar and {sup 38}Ar have been performed at low energy and backward angle to determine the distribution of {ital M}1 and {ital M}2 strength in these nuclei. The total observed {ital M}1 strength in {sup 36}Ar is approximately 93% of that predicted in the measured energy region by shell-model calculations using effective {ital M}1 operators. In {sup 38}Ar, the single strong {ital M}1 transition predicted by shell-model calculations was not observed. Instead, a number of weak transitions were observed, with total {ital M}1 strength equal to about 134% of the predicted strength.

Using inelastic electron scattering, several isobaric analog 1/sup +/ states between 9 and 13 MeV excitation in /sup 58/Ni and /sup 60/Ni have been found. They are identified as components of the T/sub 0/ + 1 giant M1 state in /sup 58/,/sup 60/Ni. (AIP)

F-spin admixtures are predicted in the non-yrast states of $^{154}\mathrm{Gd}$. The neutron-proton interacting boson model boson quadrupole transition densities are determined from electron scattering and are shown to have important F-spin vector effects.

The orbital current and spin contributions to isovector $M1$ excitations in light nuclei are studied microscopically by combining information from inelastic electron scattering at small momentum transfers with that obtained from recent measurements of ($p$,$n$) cross sections at forward angles. The ($p$,$n$) reaction is studied within the distorted-wave approximation using a $G$-matrix interaction and shell model wave functions and the ($e$,${e}^{\ensuremath{'}}$) scattering is calculated in a plane wave approximation.NUCLEAR REACTIONS Charge exchange scattering, ${E}_{p}=62$ MeV, cross sections; inelastic electron scattering; targets $^{12}\mathrm{C}$, $^{24}\mathrm{Mg}$, $^{28}\mathrm{Si}$.

The E4 form factor for inelastic electron scattering to the first ${4}^{+}$ state of $^{32}\mathrm{S}$ predicted from a systematic shell-model treatment of ${0}^{+}$\ensuremath{\rightarrow}${4}^{+}$ transitions in the A=18\char21{}38 region is found to be in excellent agreement with experiment. This shell-model prediction is quite different from recent deformed Hartree-Fock predictions for the same transition. Corresponding predictions for other doubly-even nuclei in the 0d,1s shell are also presented and discussed.

Inelastic electron scattering is shown to be a very powerful tool to study the structure of shell-model nuclei, since the form factors are very sensitive to small admixtures of different orbitals. For instance in our Ca40 case admixtures of only 1% 1p32 orbital in the pure f72 orbital produce strong changes in the form factors. Thus, inelastic electron scattering will shed light on the question of "deformed states" in Ca40. Also it is pointed out that "effective" multipole matrix elements can be extracted. In turn, those matrix elements can be used for structure analysis of shell-model nuclei by giving information on which admixtures should be included to reproduce them. NUCLEAR STRUCTURE Ca40; calculated form factors for inelastic electron scattering.

Inelastic electron scattering form factors were measured for the even-parity states of $^{27}\mathrm{Al}$ below 7 MeV. The data span a momentum transfer range of $q\ensuremath{\simeq}0.57\ensuremath{-}2.80$ ${\mathrm{fm}}^{\ensuremath{-}1}$. Separate longitudinal and transverse information was obtained, especially for the lowest-energy excitations. For excitations below 3.7 MeV, the longitudinal form factors were found to be well described by shell model calculations provided appropriate effective charges were introduced. These effective charges appear to exhibit little dependence on momentum transfer up to $q\ensuremath{\simeq}2$ ${\mathrm{fm}}^{\ensuremath{-}1}$. In contrast, effective charges or magnetic moments were not required to account for the corresponding transverse form factors. The shell model was somewhat less successful in its description of the higher-energy excitations, although tentative ${J}^{\ensuremath{\pi}}$ assignments were made for some currently ambiguous states on the basis of a comparison with the theoretical predictions.

The $E2$ properties and excitation energies of low-lying states in $^{24}\mathrm{Mg}$, $^{26}\mathrm{Mg}$, $^{30}\mathrm{Si}$, and $^{32}\mathrm{S}$ are calculated using the adiabatic model of a triaxially deformed rotor. The results are compared with those of recent shell-model calculations and strong similarity is found for both $^{24}\mathrm{Mg}$ and $^{32}\mathrm{S}$ with nearly the same deformation parameters in the adiabatic model. The strength for isovector $M1$ excitation, pertinent to results of inelastic electron scattering, is also calculated using the closure sum rule.

Elastic and inelastic electron scattering from several orientations of completely aligned 10B, repre-sented by harmonic oscillator and Tassie model fits of unoriented experimental data, is calculated and compared with scattering from the unoriented target. Results show large effects due to orientation.

In inelastic electron scattering, form factors are measured for the 1.115 MeV level (${J}^{\ensuremath{\pi}}$${=(5/2)}^{\mathrm{\ensuremath{-}}}$) in $^{65}\mathrm{Cu}$. This transition from the ground state (${J}^{\ensuremath{\pi}}$${=(3/2)}^{\mathrm{\ensuremath{-}}}$) is predominantly longitudinal, with B(E2,k)\ensuremath{\uparrow} =290\ifmmode\pm\else\textpm\fi{}20 ${e}^{2}$${\mathrm{fm}}^{4}$. In the framework of a model calculation, the M1 strength is deduced to be B(M1,k)\ensuremath{\uparrow}=0.12\ifmmode\pm\else\textpm\fi{}0.03${\ensuremath{\mu}}_{\mathrm{N}}$ 2 [${\ensuremath{\Gamma}}_{\ensuremath{\gamma}}$(M1)=1.3\ifmmode\pm\else\textpm\fi{}0.4 meV].

Inelastic electron scattering from high-lying ${6}^{+}$ states in the Ni isotopes has been measured. These states are interpreted as core-excited states.