11Be(beta-p), a quasi-free neutron decay?

K. Riisager; O. Forstner; M. J. G. Borge; J. A. Briz; M. Carmona-Gallardo; L. M. Fraile; H. O. U. Fynbo; T. Giles; A. Gottberg; A. Heinz; J. G. Johansen; B. Jonson; J. Kurcewicz; M. V. Lund; T. Nilsson; G. Nyman; E. Rapisarda; P. Steier; O. Tengblad; R. Thies; S. R. Winkler

doi:10.1016/j.physletb.2014.03.062

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arXiv · 1402.1645

11Be(beta-p), a quasi-free neutron decay?

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Abstract

We have observed beta-delayed proton emission from the neutron-rich nucleus 11Be by analysing a sample collected at the ISOLDE facility at CERN with accelerator mass spectrometry (AMS). With a branching ratio of (8.4 +- 0.6) 10^{-6} the strength of this decay mode, as measured by the B(GT)-value, is unexpectedly high. The result is discussed within a simple single-particle model and could be interpreted as a quasi-free decay of the 11Be halo neutron into a single-proton state.

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K. Riisager, O. Forstner, M. J. G. Borge, J. A. Briz, M. Carmona-Gallardo, L. M. Fraile, H. O. U. Fynbo, T. Giles, A. Gottberg, A. Heinz, J. G. Johansen, B. Jonson, J. Kurcewicz, M. V. Lund, T. Nilsson, G. Nyman, E. Rapisarda, P. Steier, O. Tengblad, R. Thies, S. R. Winkler. 2014-02-07. 11Be(beta-p), a quasi-free neutron decay?. https://doi.org/10.1016/j.physletb.2014.03.062

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