Direct proton decay and microscopic structure of the spin-dipole resonance in208Bi

Abstract
The microscopic structure of the spin-dipole resonance (SDR) at Ex=21.1MeV in 208Bi has been investigated in the 208Pb(3He,t)208Bi reaction at E(3He)=450MeV and very forward scattering angles. Protons emitted due to the decay of the SDR were measured in solid-state detectors in coincidence with tritons detected with the high resolution magnetic spectrometer Grand Raiden. The total and partial branching ratios for proton decay from the SDR to the residual neutron-hole states in 207Pb have been measured. The deduced escape widths are found to be in good agreement with recent theoretical estimates.