Nuclear spreading widths of particle-vibration (1/2)+ doorway resonances in 207Pb and 209Pb

The nuclear spreading widths of the ²⁰⁷Pb and ²⁰⁹Pb 1/2⁺ doorway resonances are calculated in a particle-vibration model. The hallway states are of the particle---two-photon type. The fine structure in ²⁰⁷Pb is essentially due to the availability of many hallways (some with large matrix elements) and their proximity to the doorway. The ²⁰⁷Pb and ²⁰⁹Pb 1/2⁺ doorway spreading widths are found to be in line with the experimental situation.