Observation of bound and unbound 1- states in 208Pb by particle spectroscopy

Using the Q3D magnetic spectrograph of the Maier-Leibnitz-Labaratorium at Garching (Germany), experiments on the Pb-208(d, d'), the Pb-207(d,p), the resonant and the Hon-resonant Pb-208(p,p') reactions were performed. The Pb-208(p,p') reaction was investigated near all seven known isobaric analog resonances in Bi-209. The excitation energies of about 300 states in Pb-208 at E-x < 8MeV were determined with an accuracy of about 100 eV. The mean distance between states in Pb-208 is about 10 keV up to the neutron threshold (S(n) = 7368keV). The number of 1(-) states observed by particle spectroscopy up to the proton threshold (S (p) = 8.00 MeV) is close to the number predicted by the schematic Aell model without residual interaction. The structure of several 1(-) states is deduced from particle spectroscopy. Four out of the seven lowest 1(-) states contain about 80% strength of a single configuration.