Measurement ofK−-Mesonic X-Ray Spectra of Medium and Heavy Elements

Abstract

Lines of the kaonic x-ray spectra of 24 elements ranging from $Z=17\mathrm{}$ to $Z=92\mathrm{}$ have been measured. Kaons are absorbed at the nuclear surface from circular orbits. The sudden cutoff of transitions to successively lower principal quantum numbers at certain values of $Z$ indicates that nuclear matter (probably neutrons) extends above the conventional nuclear surfaces. A peak in one of the spectra corresponds to x rays from ${\Sigma }^{-}$-hyperonic atoms.