Capture of negative mesons in liquid helium

Abstract

Estimates are made of the rates for the de-excitation of (π-, α) and (K-, α) atoms in liquid helium. An estimate is also made of the rate of nuclear capture of K- mesons from high s states. The calculated Auger and radiative rates give total cascade times which are roughly 5 times shorter than the experimental values. The approximations which are used are such that this is regarded as satisfactory agreement. For principal quantum number 21 ≤ n ≤ 24 the Auger rate for (K-, α) atoms is approximately equal to the rate for nuclear absorption. The calculations indicate that the amount of K- absorption from high s states may not be negligibly small.