High Resolution Study of the g9/2Isobaric Analogue State in61Cu

Abstract

the g 9/2 isobaric analogue State (IAS) in 61 Cu has been investigated by the 60 Ni(p, p) 60 Ni and (p, γ) 61 Cu reaction using high energy-resolution (overall Δ E ≃350 eV)proton beams. Resonances at E p (lab.)=3723, 3732, 3737 and 3743 keV are identified as fragments of the IAS of the g 9/2 atate in 61 Ni. Proton widths and radiative widths of these isobaric analogue resonances (IAR's) are deduced using a multi-level R-matrix code. Gamma ray spectra and γ-ray angular distributions from these IAR's have been measured with a Ge(Li) detector. Primary γ-ray branching rations are presented. The IAS to anti-IAS (AIAS) M1 transition strengh is deduced to be 0.36±0.08 W.U. and is compared with a simple shell model prediction.