Mapping quadrupole collectivity in the Cd isotopes: The breakdown of harmonic vibrational motion

• Main Authors: Garrett, P. E., TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T2A3, Green, K. L., Bangay, J., Varela, A. Diaz, Sumithrarachchi, C. S., Bandyopadhyay, D. S., Bianco, L., Demand, G. A., Finlay, P., Grinyer, G. F., Leach, K. G., Phillips, A. A., Schumaker, M. A., Svensson, C. E., Wong, J., Austin, R. A. E., Colosimo, S., Ball, G. C., Garnsworthy, A. B., Hackman, G.
• Format: Conference Proceeding
• Language: English
• Subjects: ANGULAR MOMENTUM; BETA DECAY; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; BETA-PLUS DECAY RADIOISOTOPES; BOSONS; CADMIUM ISOTOPES; COLLECTIVE MODEL; CONFIGURATION; DECAY; E2-TRANSITIONS; ELECTRON CAPTURE RADIOISOTOPES; ENERGY LEVELS; ENERGY RANGE; ENERGY-LEVEL TRANSITIONS; EXCITATION; EXCITED STATES; HARMONIC OSCILLATORS; HOURS LIVING RADIOISOTOPES; IN-BEAM SPECTROSCOPY; INDIUM 112; INDIUM ISOTOPES; INTERMEDIATE MASS NUCLEI; INTERNAL CONVERSION RADIOISOTOPES; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; LIFETIME; MATHEMATICAL MODELS; MEV RANGE; MINUTES LIVING RADIOISOTOPES; MULTIPOLE TRANSITIONS; NUCLEAR DECAY; NUCLEAR MODELS; NUCLEAR PHYSICS AND RADIATION PHYSICS; NUCLEAR POTENTIAL; NUCLEI; ODD-ODD NUCLEI; PARTICLE PROPERTIES; POTENTIALS; RADIOISOTOPES; SILVER 112; SILVER ISOTOPES; SPECTROSCOPY; SPHERICAL CONFIGURATION; SPIN; VIBRATIONAL STATES
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.3628381

The stable Cd isotopes have long been used as paradigms for spherical vibrational motion. Extensive investigations with in-beam {gamma} spectroscopy have resulted in very-well-established level schemes, including many lifetimes or lifetime limits. A programme has been initiated to complement these studies with very-high-statistics {beta} decay using the 8{pi} spectrometer at the TRIUMF radioactive beam facility. The decays of {sup 112}In and {sup 112}Ag have been studied with an emphasis on the observation of, or the placement of stringent limits on, low-energy branches between potential multi-phonon levels. A lack of suitable 0{sup +} or 2{sup +} three-phonon candidates has been revealed. Further, the sum of the B(E2) strength from spin 0{sup +} and 2{sup +} states up to 3 MeV in excitation energy to the assigned two-phonon levels falls far short of the harmonic-vibrational expectations. This lack of strength points to the failing of collective models based on vibrational phonon structures.