Gamma Strength from Quasi-Continuum Lifetimes using 56Fe(p,p')
A new experimental method is presented to normalize the Gamma Strength Function (GSF) using proton-γ coincidences from 56 Fe(p,p’γ) with an excitation dependent variation of the Doppler Shift Attenuation Method where lifetimes of quasi-continuum states delay low-lying γ-ray transitions by an amount inversely proportional to the GSF magnitude. The E-∆E scintillator array Phoswich Wall measures proton energies which designate initial nuclear excitation energy. The γ-ray tracking spectrometer GRETINA measures signature γ-ray transitions which designate the fed low-lying level. Doppler shift indicates γ-ray cascade time if comparable to the nuclear stopping time. Results provide the first 56 Fe GSF normalization.