Antihydrogen formation in laser-assisted antiproton-positronium collision

We study the charge transfer between a positronium and an antiproton in the presence of a laser field. The interactions of positronium and antihydroge n with the laser field are treated to first order as time-dependent perturb ations. The wavefunction of the ejected electron is described by the Volkov state which makes the scattering matrix decompose into a series of sub-amp litudes for multiphoton processes. The cross section for antihydrogen forma tion, and its dependences on laser parameters (intensity, frequency and pol arization direction) are discussed.