Positronium-Atom Collisions

نویسندگان

  • H. R. J. Walters
  • A. C. H. Yu
  • Sharon Gilmore
چکیده

New results are presented for Ps(1s) scattering by H(1s), He(1S) and Li(2s). Calculations have been performed in a coupled state framework, usually employing pseudostates, and allowing for excitation of both the Ps and the atom. In the Ps(1s)H(1s) calculations the H− formation channel has also been included using a highly accurate H− wave function. Resonances resulting from unstable states in which the positron orbits H− have been calculated and analysed. The new Ps(1s)-He(1S) calculations still fail to resolve existing discrepancies between theory and experiment at very low energies. The possible importance of the Ps− formation channel in all three collision systems is discussed.

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تاریخ انتشار 2004