Search

Nuclear chirality has been intensively studdied for the last several years in the context of experimental as well as theoretical approach. Characteristic gamma selection rules have been predicted for the strong chiral symmetry breaking limit that has been observed in Cs isotopes. The presented analysis shows that the gamma selection rules cannot be attributed only to chiral symmetry breaking. The selection rules relate to structural composition of the chiral rotational bands, i.e., to odd particle configuration and the deformation of the core. [ABSTRACT FROM AUTHOR]

The decay of the $\ensuremath I^{\pi}=K^{\pi}=8^{-}$ isomeric state at 2340keV in 132Ce has been investigated in the 120Sn(16O, 4n)132Ce reaction. The measurements were carried out in e - $ \gamma$ and $ \gamma$ - $ \gamma$ coincidence modes using an electron spectrometer coupled to the OSIRIS II gamma-ray array at the Heavy Ion Laboratory of the University of Warsaw. Experimentally obtained internal conversion coefficients for the $\ensuremath 8^{-} \rightarrow 6^{+}$ and $\ensuremath 8^{-} \rightarrow 5^{+}$ transitions allowed the multipolarities, mixing ratios, reduced transition probabilities and hindrance factors to be determined. [ABSTRACT FROM AUTHOR]

Properties of chiral bands in an odd-odd nucleus, which is treated as a system of an even-even core and a pair of particles in the πh11/2 ⊗ υh11/2 -1 configuration, are calculated in the frame of the Core-Particle-Hole Coupling (CPHC) model with either a rigid triaxial or a soft core. The results of calculations for the two different cores are compared. The properties of the nucleus with the rigid, maximally triaxial ( γ = 30°and with the entirely soft core are qualitatively very similar. [ABSTRACT FROM AUTHOR]

Lifetimes of the yrast levels with spins I π = 23/2− to 39/2− in 129La produced via the 120Sn(14N, 5 n) reaction at a beam energy of 77MeV have been measured by the Doppler shift attenuation method. The properties of the studied levels belonging to the πh11/2 band were compared with the theoretical predictions obtained in the framework of the core quasi-particle coupling model. It is suggested that the rigid-rotor model used to describe the cores is too simplified as the even-even nuclei from the A ∼ 130 region are susceptible to shape deformation. Reasonable agreement was obtained with the phenomenological cores based on the experimental data of 128Ba. [ABSTRACT FROM AUTHOR]

The phenomenon of chiral symmetry breaking is discussed and a review of a wide spectrum of the experimental data is given. In addition to the basic description of this phenomenon an analysis of the level schemes and electromagnetic properties observed in nuclei expected to show the chiral symmetry breaking is presented. [ABSTRACT FROM AUTHOR]

Lifetimes of the h[sub 11/2] decoupled band in [sup 131]La and supposed chiral bands in odd-odd [sup 132]La have been measured using the Doppler Shift Atenuation method. The properties of all bands have been calculated in terms of the Core Quasi Particle Coupling and Core Particle Hole Coupling models by using in both cases the same phenomenological core of [sup 130]Ba. A new band in [sup 132]La has been found. [ABSTRACT FROM AUTHOR]

The previously accepted spin values of the 991 and 1599 keV levels in 140Sm have been revised and established as 2+ and 0(+), respectively. The γ-γ angular correlation method was used to determine the new spin values. The excited low-spin levels in 140Sm were populated in the 140Eu→ 140Sm and 140Gd 140Eu→ 140Sm decays. The 140Gd and 140Eu nuclei were produced in the 112Cd + 32S reaction at a beam energy of 155 MeV. [ABSTRACT FROM AUTHOR]