0000000000336073
AUTHOR
M. Balodis
Transfer and neutron capture reactions toIr194as a test of Uν(6/12)⊗Uπ(6/4)supersymmetry
The structure of $^{194}\mathrm{Ir}$ is investigated via ($n,\ensuremath{\gamma}),(n,{e}^{\ensuremath{-}}),(d,p)$, and ($\stackrel{\ensuremath{\rightarrow}}{d},\ensuremath{\alpha}$) spectroscopy. The use of different methods leads to an almost complete level scheme up to high excitation energies including \ensuremath{\gamma}-decay and spin-parity assignments. A reanalysis of the formerly published ($n,\ensuremath{\gamma}$) data was triggered by our new ($d,p$) and ($\stackrel{\ensuremath{\rightarrow}}{d},\ensuremath{\alpha}$) transfer reactions. The experimental level scheme is compared to predictions using extended supersymmetry. Herein, the classification of states was done according to q…
Gamma bands in doubly odd rhenium and iridium nuclei
Structure of the |K ± 2| bands in doubly-odd nuclei belonging to the transitional deformation region at A∼190 is discussed. Relation of these quasi gamma-bands with the non-axial deformation of the parent two- quasiparticle configurations is studied. Using available experimental information, new tentative |K ± 2| bands are proposed in 188 Re, and 192,194 Ir nuclei. Coexistence of two-quasiparticle states with different deformation modes is considered in the case of 188 Re and 194 Ir.
Low-lying levels of 188Re nucleus from γγ-coincidence measurements
Low–high and low–low energy γγ-coincidences, following the Re187(n,γ)Re188 reaction with thermal neutrons, have been measured. Spectra have been recorded in the energy range from 50 to 2600 keV, and from 4500 to 6500 keV. The earlier known 188Re level scheme is corrected and extended up to ∼800 keV excitation energy and 62 levels by including 20 new levels. For 11 levels, the earlier interpretation has been changed. The complete level scheme is presented for up to ∼400 keV energy and spins ⩽5. Core plus two-quasiparticles model calculations have been performed. Some 188Re two-quasiparticle states display features indicating the nuclear shape phase transition from axial-deformation to γ-soft…
Levels of 188Re nucleus populated in thermal neutron capture reaction
Abstract Levels of 188 Re populated in thermal neutron capture reaction with enriched 187 Re targets have been studied. Single γ -ray spectrum of 188 Re, measured with the high-resolution crystal diffraction spectrometer GAMS5, as well as γγ -coincidence experiments performed with high efficiency Ge detectors, allowed to develop model-independent level scheme of the doubly-odd 188 Re nucleus up to ∼ 1.5 MeV excitation energy. Analysis of the established 188 Re level scheme in terms of the quasiparticle-plus-rotor model indicates coexistence of axially-deformed and triaxial structures in the energy range above 400 keV.
New supersymmetric quartet of nuclei in the A ∼ 190 mass region
We present evidence for a new supersymmetric quartet in the A=190 region of the nuclear mass table. New experimental information on transfer and neutron capture reactions to the odd-odd nucleaus 194 Ir strongly suggests the existence of a new supersymmetric quartet, consisting of the 192,193 Os and 193,194 Ir nuclei. We make explicit predictions for the odd-neutron nucleus 193 Os, and suggest that its spectroscopic properties be measured in dedicated experiments.
Levels of two-particle and gamma bands in 192 Ir
Abstract Level scheme of the transitional doubly odd nucleus 192 Ir is analysed in detail up to about 530 keV energy using earlier published experimental data of neutron capture and particle transfer reactions. A number of new levels are proposed. Obtained 192 Ir level scheme is interpreted in terms of particle-plus-rotor coupling model. It is shown that the long-lived 241 year isomer of 192 Ir has spin-parity 11 − , just like the analogous states in neighbouring 190,194 Ir.