Pramana

, Volume 66, Issue 2, pp 415–422 | Cite as

Coulomb—Born—Oppenheimer approximation in Ps—H scattering

  • Hasi Ray
Article
Received:
Revised:
Accepted:

Abstract

To improve the Coulomb-Born approximation (CBA) theory of ionization in positronium (Ps) and atom scattering, the effect of exchange is introduced. The nine-dimensional exchange amplitude for ionization of Ps in Ps—H scattering is reduced to a two-dimensional integral using the present Coulomb-Born-Oppenheimer approximation (CBOA). The methodology is extremely useful to evaluate ionization parameters for different target systems and for different types of ionization processes. It is then applied to evaluate the Ps-ionization cross-section and to estimate the effect of exchange on Psionization in Ps-H system. We establish the importance of exchange at lower energy region.

Keywords

Positronium ionization exchange electron-spin continuum Coulomb wave function 

PACS Nos

36.10.Dr 34.70.+e 82.30.Gg 95.30.Dr 
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Copyright information

© Indian Academy of Sciences 2006

Authors and Affiliations

  • Hasi Ray
    • 1
  1. 1.Department of PhysicsIndian Institute of Technology RoorkeeRoorkeeIndia

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