High-Statistics Study of the β⁺/EC-Decay of ¹¹⁰In

¹ Department of Physics, University of Guelph, Guelph, ON, N1G2W1, Canada
² TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T2A3 Canada
³ Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A1S6, Canada
⁴ Katholieke Universiteit Leuven, B-3001, Leuven, Belgium
⁵ School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
⁶ Department of Physics, University of the Western Cape, P/B X17, Bellville ZA-7535, South Africa
⁷ National Superconducting Cyclotron Center, Michigan State University, East Lansing, MI 48824, USA
⁸ Department of Chemistry and Physics & Astronomy, University of Kentucky, Lexington, KY, 40506-0055, USA

^a e-mail: adiazvar@uoguelph.ca

Published online: 20 March 2014

Abstract

A study of the ¹¹⁰In β⁺/EC decay was performed at the TRIUMF Isotope Separator and Accelerator (ISAC) facility to probe the nuclear structure of ¹¹⁰Cd. The data were collected in scaled-down γ-ray singles, γ − γ coincidence, and γ-electron coincidence mode. The data were sorted and a random-background subtracted γ − γ matrix was created containing a total of 850 million events. We expanded the level scheme of ¹¹⁰Cd significantly by identifying 75 levels under 3.8 MeV, including 12 new ones, and increased the number of previously observed transitions from these levels to 273. The γ-ray branching intensities have been extracted through an analysis of the coincidence intensities. The branching ratios were combined with a reanalysis of lifetimes measurements obtained in an (n, n'γ) reaction with monoenergetic neutrons for the calculation of B(E2) values and these results have lead to the proposal of a γ-soft rotor, or O(6) nucleus, rather than a vibrational, or U(5) pattern for the nature of the low-lying, low-spin levels in ¹¹⁰Cd.