Electron- and photon-induced proton knockout from 209Bi

Cross sections have been measured for the Bi-209(e,e'p)Pb-208 and Bi-209(gamma ,p)Pb-208 reactions using electrons at E-e = 293 and 412 MeV, and tagged photons at mean E(gamma)similar to 43.7 and similar to 52.0 MeV, respectively. The Bi-209(e.e'p)Pb-208 results are compared to complete distorted wave impulse approximation calculations, from which it is deduced that a model of Bi-209 based on a 1h(9/2) proton orbiting an inert Pb-208 core has a high degree of validity. The interpretation of the Bi-209(gamma ,p)Pb-208 results makes use of the (e,e'p) results to constrain the calculation of the direct knockout contribution. Using this approach, a comparison of the Bi-209(gamma ,p)Pb-208 data to various calculations with and without meson exchange contributions shows that the enhancement of the (gamma ,p) cross section due to meson exchange is small. This is in contrast to results obtained for light nuclei, but in agreement with results for heavier nuclei.