Inelastic scattering of the neutron-rich nucleus Be-12 on lead and carbon t
argets has been studied by measuring de-excitation gamma rays in coincidenc
e with scattered Be-12. The strong gamma -ray transition from the state at
E-x = 2.68(3) MeV following El Coulomb excitation was observed for the lead
target, leading to an assignment of J(pi) = 1(-) for the excited state. Th
e low excitation energy of this intruder 1(-) state and the deduced large B
(El; O-g.s.(+) --> 1(-)) value of 0.051(13)e(2) fm(2) provide a consistent
picture of the N = 8 shell melting in Be-12. (C) 2000 Elsevier Science B.V.
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