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arXiv · 1305.0677

Observation of a low-lying neutron-unbound state in 19C

M. Thoennessen·S. Mosby·N. S. Badger·T. Baumann·D. Bazin·M. Bennett·J. Brown·G. Christian·P. A. DeYoung·J. E. Finck·M. Gardner·E. A. Hook·B. Luther·D. A. Meyer·M. Mosby·W. F. Rogers·J. K. Smith·A. Spyrou·M. J. Strongman
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Abstract

Proton removal reactions from a secondary 22N beam were utilized to populate unbound states in neutron-rich carbon isotopes. Neutrons were measured with the Modular Neutron Array (MoNA) in coincidence with carbon fragments. A resonance with a decay energy of 76(14) keV was observed in the system 18C+n corresponding to a state in 19C at an excitation energy of 653(95)keV. This resonance could correspond to the first 5/2+ state which was recently speculated to be unbound in order to describe 1n and 2n removal cross section measurements from 20C.

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M. Thoennessen, S. Mosby, N. S. Badger, T. Baumann, D. Bazin, M. Bennett, J. Brown, G. Christian, P. A. DeYoung, J. E. Finck, M. Gardner, E. A. Hook, B. Luther, D. A. Meyer, M. Mosby, W. F. Rogers, J. K. Smith, A. Spyrou, M. J. Strongman. 2013-05-03. Observation of a low-lying neutron-unbound state in 19C. https://doi.org/10.1016/j.nuclphysa.2013.05.001

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