Coulomb excitation and breakup of π+π−-atoms at high energies Original Research Article

We develop a semi-classical theory for the excitation and breakup of a π+π−-atom moving at relativistic energies in the screened Coulomb field of a nucleus. Cross sections for various π+π−-atomic transitions and target nuclei are evaluated analytically and numerically in first-order perturbation theory. Anticipating further refinement of our theory, special attention is devoted to identifying the various approximations and estimating their associated errors.