Properties of 187Ta revealed through isomeric decay

Abstract

Mass-separated 187Ta in a high-spin isomeric state has been produced for the first time by multi-nucleon transfer reactions, employing an argon gas stopping cell and laser ionisation. Internal gamma rays revealed a 7.3 s isomer at 1778 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer decay reduced E2 hindrance factor of 27 supports the interpretation that axial symmetry is approximately conserved.

arXiv comment5 pages, 5 figures

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Cited by in corpus (4)

• Astromers in the radioactive decay of r-process nuclei
• First direct observation of isomeric decay in neutron-rich odd-odd ${}^{186}$Ta
• Direct observation of $\beta$ and $\gamma$ decay from a high-spin long-lived isomer in ${}^{187}$Ta
• Sensitivity of Neutron-Rich Nuclear Isomer Behavior to Uncertainties in Direct Transitions