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arXiv · 1203.1369

Spectroscopy of neutron-unbound $^{27,28}$F

G. Christian·N. Frank·S. Ash·T. Baumann·P. A. DeYoung·J. E. Finck·A. Gade·G. F. Grinyer·B. Luther·M. Mosby·S. Mosby·J. K. Smith·J. Snyder·A. Spyrou·M. J. Strongman·M. Thoennessen·M. Warren·D. Weisshaar·A. Wersal
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Abstract

The ground state of $^{28}$F has been observed as an unbound resonance $2\underline{2}0$ keV above the ground state of $^{27}$F. Comparison of this result with USDA/USDB shell model predictions leads to the conclusion that the $^{28}$F ground state is primarily dominated by $sd$-shell configurations. Here we present a detailed report on the experiment in which the ground state resonance of $^{28}$F was first observed. Additionally, we report the first observation of a neutron-unbound excited state in $^{27}$F at an excitation energy of $25\underline{0}0 (2\underline{2}0)$ keV.

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G. Christian, N. Frank, S. Ash, T. Baumann, P. A. DeYoung, J. E. Finck, A. Gade, G. F. Grinyer, B. Luther, M. Mosby, S. Mosby, J. K. Smith, J. Snyder, A. Spyrou, M. J. Strongman, M. Thoennessen, M. Warren, D. Weisshaar, A. Wersal. 2012-03-07. Spectroscopy of neutron-unbound $^{27,28}$F. https://doi.org/10.1103/physrevc.85.034327

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