Competing single-particle and collective states in the low-energy structure of 113I
Taylor, M. J., Cullen, D., Procter, M. G., Bäck, T., Cederwall, B., Doncel, M., . . . Xu, F. R. (2013). Competing single-particle and collective states in the low-energy structure of 113I. Physical Review C, 88 (5), 054307. doi:10.1103/PhysRevC.88.054307
Published inPhysical Review C
© 2013 American Physical Society. Published in this repository with the kind permission of the publisher.
To understand the low-energy structure of the neutron deficient iodine isotopes, lifetimes for the low-lying 9/2+ and 11/2+ positive-parity states in 113I have been measured as τ = 28(4) ps and τ = 3.7(7) ps, respectively. The lifetime for the 11/2− state, which feeds the 9/2+ and 11/2+ states, was remeasured with improved accuracy as τ = 216(7) ps. The reduced transition probability, B(E2) = 32(5) W.u., for the 9/2+ → 5/2+ transition agrees with that calculated within the shell model using a Hamiltonian based on the charge-dependent Bonn nucleon-nucleon interaction. In contrast, the much larger transition probability, B(E2) = 209(39) W.u., measured for the 11/2+ → 7/2+ transition has been interpreted, with the aid of configuration-constrained total Routhian surface calculations, as resulting from a slightly γ -soft rotor with an associated quadrupole deformation of β2 ≈ 0.18. Remarkably similar reduced E1 transition probabilities of 5.5(5) × 10−4 and 4.9(5) × 10−4 W.u. were deduced for the 11/2− → 9/2+ and 11/2− → 11/2+ transitions, respectively, which feed apparently dissimilar but competing structures. ...