TOTAL CROSS-SECTIONS FOR THE INTERACTION OF HYDROGEN-LIKE ATOMS WITH ATOMS OF A MEDIUM

The total cross sections for the Coulomb interaction of hydrogen-like atoms with atoms of a target are obtained analytically in the eikonal approximation. It is shown that, for compact atoms (whose dimensions a re much less than the dimensions of target atoms), corrections to the Born approximation are similar in structure to the Bethe-Bloch formula s for ionization losses in matter and to the Bethe-Maximon formulas fo r bremsstrahlung and pair production in the Coulomb field of an atom. In the case of scattering on targets with large Z, these corrections b ecome sizable, and their inclusion is necessary in determining the lif etimes of hydrogen-like atoms from experiments with nuclear targets.