Coulomb de-excitation of mesic hydrogen

Some aspects of the cascade of neutral exotic atoms are analysed. In particular the relevance of the Coulomb de-excitation-transitions induced by the Coulomb interaction with the surrounding atoms-is pointed out. Cross-sections and rates are calculated for μ-p and π-p atoms in hydrogen with energies ranging between 0.1 and 10 eV. The effect turns out to be dominant for n≳10 and for a large interval of pressure values. The consequence is a drastic shortening of the early stages of the cascade. When considered for π-p atoms, the effect provides a better agreement between the theoretical and experimental cascade times than that previously found. © 1978 Società Italiana di Fisica.