  An experiment measuring electroproduction of hypernuclei has been performed
in Hall A at Jefferson Lab on a $^{12}$C target. In order to increase counting
rates and provide unambiguous kaon identification two superconducting septum
magnets and a Ring Imaging CHerenkov detector (RICH) were added to the Hall A
standard equipment. An unprecedented energy resolution of less than 700 keV
FWHM has been achieved. Thus, the observed \lam{12}{B} spectrum shows for the
first time identifiable strength in the core-excited region between the
ground-state {\it s}-wave $\Lambda$ peak and the 11 MeV {\it p}-wave $\Lambda$
peak.
