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arXiv · 1812.03342

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

A. Gade·R. V. F. Janssens·J. A. Tostevin·D. Bazin·J. Belarge·P. C. Bender·S. Bottoni·M. P. Carpenter·B. Elman·S. J. Freeman·T. Lauritsen·S. M. Lenzi·B. Longfellow·E. Lunderberg·A. Poves·L. A. Riley·D. K. Sharp·D. Weisshaar·S. Zhu
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Abstract

Excited states in the neutron-rich \nuc{70}{Fe} nucleus were populated in a one-proton removal reaction from \nuc{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 \nuc{70}{Fe} is discussed in comparison to LNPS-new large-scale shell-model calculations.

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A. Gade, R. V. F. Janssens, J. A. Tostevin, D. Bazin, J. Belarge, P. C. Bender, S. Bottoni, M. P. Carpenter, B. Elman, S. J. Freeman, T. Lauritsen, S. M. Lenzi, B. Longfellow, E. Lunderberg, A. Poves, L. A. Riley, D. K. Sharp, D. Weisshaar, S. Zhu. 2018-12-08. The structure of 70Fe: Single-particle and collective degrees of freedom. https://doi.org/10.1103/physrevc.99.011301

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