Fragmentation of positronium in collision with Li ion including electron loss to the continuum

摘要

Fragmentation of ground state ortho-positronium (Ps) in collision with Li ion (Li+) is studied in the framework of post-collisional Coulomb distorted eikonal approximation (CDEA), giving special emphasis on the dynamics of the electron loss to the continuum (ELC) that occurs when the electron (e?‘’) and the positron (e?‘’+) are very close to each other in the velocity space (e?‘￡e?‘’ a‰? e?‘￡e?‘?). The present model takes account of the two-centre effect on the ejected e?‘’ which is crucial for a proper description of the ELC phenomena. Both the fully differential cross-section (TDCS) and the doubly differential cross-section (DDCS) (energy spectra) are investigated at intermediate and high incident energies. A broad distinct ELC peak centred around e?‘￡e?‘’ a‰? e?‘￡e?‘? is noted in the e?‘’ energy spectrum in contrast to the sharp ELC peak for a heavy projectile, corroborating the experimental findings. Two salient features are noted in the present study:the shift of the e?‘’ DDCS peak (summed over e?‘’+ angles) towards higher ejection energy with respect to half the residual energy of the system,