Neutron knockout of 12Be populating neutron-unbound states in 11Be

William A. Peters; T. Baumann; B. A. Brown; J. Brown; P. A. DeYoung; J. E. Finck; N. Frank; K. L. Jones; J. -L. Lecouey; B. Luther; G. F. Peaslee; W. F. Rogers; A. Schiller; M. Thoennessen; J. A. Tostevin; K. Yoneda

doi:10.1103/physrevc.83.057304

arXiv · 1104.0255

Neutron knockout of 12Be populating neutron-unbound states in 11Be

William A. Peters·T. Baumann·B. A. Brown·J. Brown·P. A. DeYoung·J. E. Finck·N. Frank·K. L. Jones·J. -L. Lecouey·B. Luther·G. F. Peaslee·W. F. Rogers·A. Schiller·M. Thoennessen·J. A. Tostevin·K. Yoneda

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Abstract

Neutron-unbound resonant states of 11Be were populated in neutron knock-out reactions from 12Be and identified by 10Be-n coincidence measurements. A resonance in the decay-energy spectrum at 80(2) keV was attributed to a highly excited unbound state in 11Be at 3.949(2) MeV decaying to the 2+ excited state in 10Be. A knockout cross section of 15(3) mb was inferred for this 3.949(2) MeV state suggesting a spectroscopic factor near unity for this 0p3/2- level, consistent with the detailed shell model calculations.

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William A. Peters, T. Baumann, B. A. Brown, J. Brown, P. A. DeYoung, J. E. Finck, N. Frank, K. L. Jones, J. -L. Lecouey, B. Luther, G. F. Peaslee, W. F. Rogers, A. Schiller, M. Thoennessen, J. A. Tostevin, K. Yoneda. 2011-04-01. Neutron knockout of 12Be populating neutron-unbound states in 11Be. https://doi.org/10.1103/physrevc.83.057304

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