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arXiv · 1605.09723

Evidence of strong dynamic core excitation in $^{19}$C resonant break-up

J. A. Lay·R. de Diego·R. Crespo·A. M. Moro·J. M. Arias·R. C. Johnson
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Abstract

The resonant break-up of $^{19}$C on protons measured at RIKEN [Phys. Lett. B 660, 320 (2008)] is analyzed in terms of a valence-core model for $^{19}$C including possible core excitations. The analysis of the angular distribution of a prominent peak appearing in the relative-energy spectrum could be well described with this model and is consistent with the previous assignment of $5/2^{+}$ for this state. Inclusion of core-excitation effects are found to be essential to give the correct magnitude of the cross section for this state. By contrast, the calculation assuming an inert $^{18}$C core is found to largely underestimate the data.

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J. A. Lay, R. de Diego, R. Crespo, A. M. Moro, J. M. Arias, R. C. Johnson. 2016-05-31. Evidence of strong dynamic core excitation in $^{19}$C resonant break-up. https://doi.org/10.1103/physrevc.94.021602

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