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Discovery of a new isomeric state in $^{68}$Ni: Evidence for a highly-deformed proton intruder state

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 نشر من قبل Aurore Dijon
 تاريخ النشر 2012
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 تأليف A. Dijon




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We report on the observation of a new isomeric state in $^{68}$Ni. We suggest that the newly observed state at 168(1) keV above the first 2$^+$ state is a $pi(2p-2h)$ 0$^{+}$ state across the major Z=28 shell gap. Comparison with theoretical calculations indicates a pure proton intruder configuration and the deduced low-lying structure of this key nucleus suggests a possible shape coexistence scenario involving a highly deformed state.



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