The Halo of 14Be

M. Labiche; N. A. Orr; F. M. Marques; J. C. Angelique; L. Axelsson; B. Benoit; U. C. Bergmann; M. J. G. Borge; W. N. Catford; S. P. G. Chappell; N. M. Clarke; G. Costa; N. Curtis; A. D'Arrigo; E. de Goes Brennand; O. Dorvaux; G. Fazio; M. Freer; B. R. Fulton; G. Giardina; S. Grevy; D. Guillemaud-Mueller; F. Hanappe; B. Heusch K. L. Jones; B. Jonson; C. Le Brun; S. Leenhardt; M. Lewitowicz; M. J. Lopez; K. Markenroth; A. C. Mueller; T. Nilsson; A. Ninane; G. Nyman; F. de Oliveira; I. Piqueras; K. Riisager; M. G. Saint Laurent; F. Sarazin; S. M. Singer; O. Sorlin; L. Stuttge

arXiv · nucl-ex/0006003

The Halo of 14Be

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Abstract

The two-neutron halo nucleus 14Be has been investigated in a kinematically complete measurement of the fragments (12Be and neutrons) produced in dissociation at 35 MeV/nucleon on C and Pb targets. Two-neutron removal cross-sections, neutron angular distributions and invariant mass spectra characteristic of a halo were observed and the electromagnetic (EMD) contributions deduced. Comparison with three-body model predictions indicate that the halo wavefunction contains a large 2s1/2^2 admixture. The EMD invariant mass spectrum exhibited a relatively narrow structure near threshold (Edecay=1.8+/-0.1 MeV, Gamma = 0.8+/-0.4 MeV) consistent with a soft-dipole excitation.

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M. Labiche, N. A. Orr, F. M. Marques, J. C. Angelique, L. Axelsson, B. Benoit, U. C. Bergmann, M. J. G. Borge, W. N. Catford, S. P. G. Chappell, N. M. Clarke, G. Costa, N. Curtis, A. D'Arrigo, E. de Goes Brennand, O. Dorvaux, G. Fazio, M. Freer, B. R. Fulton, G. Giardina, S. Grevy, D. Guillemaud-Mueller, F. Hanappe, B. Heusch K. L. Jones, B. Jonson, C. Le Brun, S. Leenhardt, M. Lewitowicz, M. J. Lopez, K. Markenroth, A. C. Mueller, T. Nilsson, A. Ninane, G. Nyman, F. de Oliveira, I. Piqueras, K. Riisager, M. G. Saint Laurent, F. Sarazin, S. M. Singer, O. Sorlin, L. Stuttge. 2000-06-07. The Halo of 14Be. https://arxiv.org/abs/nucl-ex/0006003

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