Resonance fluorescence from the 7.08-MeV state in 208Pb

The Doppler-broadened 7.12-MeV transition from the ¹⁹F(p, αγ)¹⁶O reaction has been used to fluoresce resonantly a level at 7.084 +/- 0.002 MeV in ²⁰⁸Pb. A spin value of J=1 has been assigned by measuring the intensity of the scattered radiation at average scattering angles of 90 and 130°. From a study of the intensity growth of the scattered radiation with increasing scatterer thickness (production experiment), the following level parameters were extracted: integrated scattering cross section σ_sdE=2.07+/-0.18 MeV mb, maximum absorption cross section σ_A=85⁺³⁶_-31 b, total level width Γ=26⁺³⁵_-12 eV, and partial width for the ground-state transition Γ₀=16⁺⁶_-4 eV. [NUCLEAR REACTIONS ²⁰⁸Pb(γ,γ'), E~7 MeV; measured σ(E_γθ). ²⁰⁸Pb deduced level Γ, Γ₀, σ_A, J. Natural Pb targets, resonance-fluorescence production experiment.]