ΔJ=1 bands built on low-lying 9/2+ states (307 keV in 119I) have been observed in odd-A 117.127I (Z=53) nuclei via (6Li, 3nγ) reactions. Calculations of the total potential energy of these nuclear states in terms of a 9/9+ Nilsson proton hole revealed minima at significant prolate deformations (ε=0.22 for 119I). The resulting excitation energies and band spacing calculations are in good agreement with experiment. The properties of these deformed 9/2+ states, which involve a 1g9/2 proton excited through the Z=50 major shell, are compared with those of the deformed 9/2+ states previously observed in odd-Sb (Z=51) nuclei.
NUCLEAR REACTIONS 114-124Sn(6Li, 3n), ELi=25-35 MeV, measured γ-γ coincidences, γ(E, θ, t); deduced level scheme in odd-A 117-127I, γ multipolarities, Jπ. Enriched targets, Ge(Li) detectors.
NUCLEAR STRUCTURE Odd-A 117-127I, calculated 9/2+ proton-hole state energies, ΔJ=1 rotational bands.
© 1977 The American Physical Society