Electrons with incident energies between 52.3 and 90.0 MeV have been scattered from the nucleus of ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$. Spectra of scattered electrons corresponding to excitation energies up to 32 MeV were observed at angles of 75° and 145°. Form factors of the states at 2.12, 4,44, 5.02, 8.57, and 8.93 MeV, and of the continuum region up to 30 MeV, have been separated into longitudinal and transverse components. The ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ dipole giant resonance is smooth relative to those of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$. A mixed $M1-E2\mathrm{}$ transition was observed at 13.0 MeV and a broad transverse resonance, possibly magnetic, was seen at 15.5 MeV.

NUCLEAR REACTIONS ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}(e, e^{\prime })$, $E=52.3-90.0\mathrm{}$ MeV, $\theta =75\mathrm{}°-145\mathrm{}°$; measured $\sigma \left(E^{\prime }\theta \right)$; deduced $B\left(E2\mathrm{}\right)\mathrm{}$, $B\left(M1\mathrm{}\right)\mathrm{}$, giant resonance differential form factors.

• Received 18 September 1974

DOI:https://doi.org/10.1103/PhysRevC.11.323