Ionization of K-electrons in solids by relativistic heavy particles

The theory of K-electron ionization probabilities by heavy relativistic particles (protons, mesons, ions) as a function of an impact parameter is treated in the virtual photon approximation. This approximation can be used to calculate the K-X-ray yield excited by channeled negative and positive particles. For negative particles there is an enhancement of the yield under channeling conditions as compared with the random yield. The present theory predicts a considerable decrease of the depth of the K-X-ray yield dip when a positive particle velocity upsilon yields c. A comparison of the theoretical results with the experiments on total ionization cross sections has been performed and the agreement is good. (author)