K− and [formula omitted] deeply bound atomic states

Abstract

The strongly absorptive optical potentials V opt which have been deduced from the strong-interaction level shifts and widths in X-ray spectra of K − and p ̄ atoms produce effective repulsion leading to substantial suppression of the atomic wave functions within the nucleus. The width of atomic levels then saturates as function of the strength of Im V opt. We find that `deeply bound' atomic states, which are inaccessible in the atomic cascade process, are generally narrow, due to this mechanism, over the entire periodic table and should be reasonably well resolved. These predictions are insensitive to V opt, provided it was fitted to the observed X-ray spectra. In contrast, the nuclear states bound by V opt are very broad and their spectrum depends sensitively on details of V opt. We discuss production reactions for K − atomic states using slow K − mesons from the decay of the φ(1020) vector meson, and the ( p ̄ ,p ) reaction for p ̄ atomic states. Rough cross section estimates are given.