No abstract

No abstract

The reorientation effect arises from the dependence of the Coulomb excitation process on the static moments of nuclear states. Various authors 1 " 4 have suggested experiments in which this effect can be singled out so that the quadrupole moment of, e.g., the first 2 + state in an even-even nucleus may be determined. The theoretical treatment of the process has so far only been carried out using second-2 ' 4 and third-order 3 perturbation expansions. The present paper describes the experimental determination of the reorientation effect in Cd 114 by an evaluation of the measured cross sections for the scattering of O 16 and He 4 ions in terms of Qo + > the quadrupole moment of the first 2 + state. The analysis has been made using a computer program which avoids the perturbation expansion.The Coulomb excitation of the 0.5578-MeV state in Cd 114 has been determined by two methods:(a) The particles backscattered from a thin target into an annular solid-state detector were recorded in coincidence with the de-excitation gamma radiation. If the efficiency of the gamma counter, the gamma-ray angular distribution, and the conversion coefficient are known, the quantity = number of de-excitations of the first 2 + state per backscattered particle can be determined through this experiment. In terms of the cross sections do^ R\ a ' is expressed in the following way: M)7 II t=2 I 1=1The index i refers to the different nuclear states indicated in Fig. 1, and the quantity / zdenotes the fraction of the decays of level i which cascade through the 0.5578-MeV level. The experimental technique used in this method has been described by de Boer, Goldring, and Winkler. 5 The O 16 and He 4 bombarding energies were chosen in such a way as to yield similar values for the adiabaticity parameter INDEX SPIN i i 1 1

No abstract

No abstract