Are there any narrow K−-nuclear states?

We performed self-consistent calculations of K−-nuclear quasi-bound states using a single-nucleon K− optical potential derived from chiral meson-baryon coupled-channel interaction models, supplemented by a phenomenological K− multinucleon potential introduced recently to achieve good fits to kaonic atom data [1]. Our calculations show that the effect of K− multinucleon interactions on K− widths in nuclei is decisive. The resulting widths are considerably larger than corresponding binding energies. Moreover, when the density dependence of the K−-multinucleon interactions derived in the fits of kaonic atoms is extended to the nuclear interior, the only two models acceptable after imposing as additional constraint the single-nucleon fraction of K− absorption at rest do not yield any kaonic nuclear bound state in majority of considered nuclei.