Isomeric decays in neutron-rich W, Os and Pt nuclei

• Relativistic energy fragmentation of a 1 GeV/nucleon Pb-208 beam was used to populate a wide range of nuclei on both sides of the valley of beta-stability. The structure of these nuclei was studied by the identification of discrete gamma-ray transitions depopulating isomeric states with lifetimes in the nano- to millisecond range. Highlights of the experiment include the first observation of gamma-ray transitions in the neutron-rich nuclei (188)TA, W-190, Re-192, Os-195, Ir-197,Ir-198, Pt-201,Pt-202. The yrast states in W-190 and Pt-202 as well as the decay out from 10-20 ns isomers in Pt-202,Pt-201 and Os-195 are discussed. The observation of the previously reported isomeric K = 35/2 states in Hf-175, W-179 and Re-181 represents the highest discrete spin states observed to date following a projectile fragmentation reaction.

Subject headings

NATURVETENSKAP  -- Fysik -- Subatomär fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Subatomic Physics (hsv//eng)

Publication and Content Type

art (subject category)

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