Inelastic transitions between close atomic levels induced by electrons and protons

Abstract

Excitation cross sections sigma and rate coefficients (v sigma ) are studied for transitions with a small resonance defect omega in electron-atom and ion-atom collisions. The universal curves for sigma and (v sigma ) are obtained in the Born approximation for dipole allowed transitions using a model potential of the type V(R)= lambda R/(R²+R₀²)³2/. The choice of effective radius R₀ is suggested. The condition of validity of the Born approximation for transitions with a small resonance defect is obtained in the form ( lambda omega /v²)²0/v<or approximately=1 where v is the velocity of the incident charged particle.