论文信息 - Invariant-mass spectroscopy of the neutron-drip line nucleus 14Be

Invariant-mass spectroscopy of the neutron-drip line nucleus 14Be

We performed an experiment of the inelastic scattering of the two neutron halo nucleus 14Be at 68 A MeV on a carbon target. Since 14Be has no bound excited state, 14Be breaks up into 12Be and two neutrons. Using the invariant-mass method, the first excited state of 14Be is clearly observed at Eex = 1.56(13) MeV. A distorted-wave Born approximation analysis is performed and the spin-parity corresponding to the peak is assigned to be Jπ = 2+. Deformation length of 14Be is extracted to be ∂C = 1.53(10) fm. These experimental results are compared with shell-model calculations.

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