A comparison of two independent measurements of the lifetime of a state in59Cu

Abstract

Two states in 59Cu populated by the reaction 58Ni(p, gamma ) at proton energies of 3547 and 1833 keV have been studied. An investigation of the gamma ray transition between the resonance states and the gamma ray decay of the lower energy resonance has yielded Gamma gamma / Gamma =0.86+or-0.04 and (2J+1) Gamma gamma Gamma p/ Gamma =0.046+or-0.005 eV for the lower resonance. The spin of the lower resonance (Ex=5219 keV) has been deduced to be 9/2 and therefore the total width of the state is 0.038+or-0.009 eV, corresponding to a lifetime tau =17.5+or-4.1 fs. The Doppler shift attenuation method used to determine the lifetime of this state yields the values 13.5+or-2 fs and 16+or-2 fs. It is concluded that, within experimental error, there is agreement between observation and standard ion energy loss theory for the case of Cu recoiling in Ni.