Nuclear (K)over-bar bound states in light nuclei -: art. no. 044005

The possible existence of deeply bound nuclear (K) over bar states is investigated theoretically for few-body systems. The nuclear ground states of a K- in He-3, He-4, and Be-8 are predicted to be discrete states with binding energies of 108, 86, and 113 MeV and widths of 20, 34, and 38 MeV, respectively. The smallness of the widths arises from their energy-level locations below the Sigmapi emission threshold. It is found that a substantial contraction of the surrounding nucleus is induced due to the strong attraction of the I=0 (K) over barN pair, thus forming an unusually dense nuclear medium. Formation of the T=0 K(-)x(3)He+(K) over bar (0)x(3)H state in the He-4 (stopped K-, n) reaction is proposed, with a calculated branching ratio of about 2%.