BETA-DECAY OF THE HALO NUCLEUS BE-14

We suggest that in a halo nucleus, the B-decay of a core may lead to t he formation of a product nucleus with a similar cluster structure. As an example, the beta-decay of Be-14 (= Be-12+n+n) is considered. Calc ulations of the B-14 spectrum within the generator coordinate method ( GCM) predict the existence of 0(+), 1(+) and 2(+) narrow states having a B-12+n+n structure and located near the two-neutron threshold. As f ollows from the calculations, the B-decay of(14)Be to the 1(+) state m ainly occurs when two halo neutrons stay far away from the core.