Test of traditional vibrational wisdom by 2 proton stripping onto targets of 108;110Pd,114Cd,115In

Abstract

The cadmium nuclei have traditionally been regarded as among the best examples of spherical vibrational nuclei. However, advances in nuclear spectroscopy have begun to detail the properties of these nuclei at the two and three vibrational phonon levels, casting doubts on the vibrational assumptions. In particular, the properties of the excited 0+n (for n 2) levels are key to any vibrational model. Excited 0+ states can arise in nuclei in association with the nucleon pairing degrees of freedom, and in model spaces with collective shape degrees of freedom. This thesis reports details of the excited 0+n levels in the even-even nuclei 110;112Cd and 116Sn, and the excited 9 2 + states in 117Sb, investigated using two-proton stripping reactions. The 108;110Pd(3He, n )110;112Cd, 114Cd(3He, n )116Sn and 115In(3He, n )117Sb reactions were investigated using AFRODITE spectrometer in conjunction with a wall of 12 plastic scintillator detectors placed 2 m away from the target chamber.