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تسجيل مستخدم جديدHindered alpha decays of heaviest high-K isomers
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To find candidates for long-lived high-K isomers in even-even Z=106-112 superheavy nuclei we study dominant alpha-decay channel of two- and four-quasi-particle configurations at a low excitation. Energies are calculated within the microscopic - macroscopic approach with the deformed Woods-Saxon potential. Configurations are fixed by a standard blocking procedure and their energy found by a subsequent minimization over deformations. Different excitation energies of a high-K configuration in parent and daughter nucleus seem particularly important for a hindrance of the alpha-decay. A strong hindrance is found for some four-quasi-particle states, particularly $K^{pi} = 20^{+}$ and/or $19^{+}$ states in $^{264-270}$Ds. Contrary to what was suggested in experimental papers, it is rather a proton configuration that leads to this strong hindrance. If not shortened by the electromagnetic decay, alpha half-lives of $sim$ 1 s could open new possibilities for studies of chemical/atomic properties of related elements.
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An isomer, with t1/2 = 35 +- 10 ns and J, Kpi = 14, 14+, has been observed in the nucleus 176W using the reaction 150Nd(30Si,4n) at a beam energy of 133 MeV. The isomer exhibits an unusual pattern of decay in which the _majority_ of the flux proceeds
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