High resolution spectroscopy of the B-12(Lambda) hypernucleus produced by the (e, e-prime K+) reaction

High energy CW electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the usefulness of the (e,e'K+) reaction. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed resolution, ~900 keV, of the 12B(hypernuclear) spectrum is the best yet attained using magnetic spectrometers. The positions of the major excitations are in agreement with theoretical predictions and the previous binding energy measurements.