Nature of the four-quasiparticle negative-parity rotational bands in 194Tl
Presented by Dr. OBED SHIRINDA on 9 Jul 2014 from 17:10 to 19:00
Type: Poster Presentation
Track: Track B - Nuclear, Particle and Radiation Physics
Board #: B.298
Three negative-parity rotational bands have been identified in the <sup>194</sup>Tl [1-3] nucleus. All three bands are associated with a four-quasiparticle πh<sub>9/2</sub> x νi<sub>13/2</sub><sup>-3</sup> configuration at high spins. Two of these bands show exceptionally close near-degeneracy in the excitation energies, and furthermore a close similarity in their other properties, e.g. alignments, B(M1)/B(E2) ratios, etc. . Based on these results the pair of four-quasiparticle negative-parity bands in <sup>194</sup>Tl was interpreted as perhaps the best chiral pair found to date . The nature of the third πh<sub>9/2</sub> x νi<sub>13/2</sub><sup>-3</sup> band, however, remains unclear. It was suggested , that this band could correspond to axially symmetric nuclear shape. As an alternative, the three bands could form a multiplet of chiral partners built on the same nucleon configuration . In this work we aim at studying further the nature of the three negative-parity bands. We used the experimental data on the lifetime measurements for these bands  and performed multi-particle-plus-triaxial rotor model (MPR)  calculations. These calculations were carried out for both triaxial (β<sub>2</sub> = 0.15, γ = 40°) and axially symmetric nuclear shape. The results will be presented and discussed.  P.L. Masiteng et al., Phys. Lett. B719, 83 (2013).  P.L. Masiteng et al., Submitted to Eur. Phys. J. A  P.L. Masiteng, PhD thesis, University of the Western Cape, (2013).  B.G. Carlsson and I. Ragnarsson, Phys. Rev. C74, 044310 (2006).
Dr. Obed Shirinda email@example.com iThemba LABS