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The structure of 70Fe: Single-particle and collective degrees of freedom

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 نشر من قبل Alexandra Gade
 تاريخ النشر 2018
  مجال البحث
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Excited states in the neutron-rich uc{70}{Fe} nucleus were populated in a one-proton removal reaction from uc{71}{Co} projectiles at 87~MeV/nucleon. A new transition was observed with the $gamma$-ray tracking array GRETINA and shown to feed the previously assigned $4^+_1$ state. In comparison to reaction theory calculations with shell-model spectroscopic factors, it is argued that the new $gamma$ ray possibly originates from the $6^+_1$ state. It is further shown that the Doppler-reconstructed $gamma$-ray spectra are sensitive to the very different lifetimes of the $2^+$ and $4^+$ states, enabling their approximate measurement. The emerging structure of uc{70}{Fe} is discussed in comparison to LNPS-new large-scale shell-model calculations.


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