Narrow deeply bound K− atomic states

Using optical potentials fitted to a comprehensive set of strong interaction level shifts and widths in K− atoms, we predict that the K− atomic levels which are inaccessible in the atomic cascade process are generally narrow, spanning a range of widths about 50–1500 keV over the entire periodic table. The mechanism for this narrowing is different from the mechanism for narrowing of pionic atom levels. Examples of such `deeply boundʹ K− atomic states are given, showing that in many cases these states should be reasonably well resolved. Several reactions which could be used to form these `deeply boundʹ states are mentioned. Narrow deeply bound states are expected also in p atoms.