γ decay to the ground state from the excitations above the neutron threshold in the Pb208(p,p′γ) reaction at 85 MeV

A new measurement of γ decay from the states above neutron threshold in Pb208 has been performed at Cyclotron Centre Bronowice Kraków, Poland. The main goal experiment was to observe ground state isoscalar giant quadrupole resonance (ISGQR). To this day, only published observation phenomenon dates back late 1980s, where branching ratio reported. At variance with existing using inelastic scattering O17, here proton is employed. In particular, data were obtained for Pb208(p,p′γ) 85 MeV beam energy, rays measured angles 8.9∘, 10.7∘, 12.5∘, and 14.3∘. By applying a similar analysis method as previous experiment, ISGQR gamma extracted data.1 MoreReceived 22 September 2021Accepted 24 December 2021Corrected 7 February 2022DOI:https://doi.org/10.1103/PhysRevC.105.014310©2022 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasCollective levelsElectromagnetic transitionsNuclear structure & decaysNucleon induced nuclear reactionsResonance reactionsProperties190 ≤ 219Nuclear Physics