Low-energy scattering of electrons on positronium atoms

We have calculated cross sections for elastic and spin-flip scattering processes of electrons on positronium atoms in the para and ortho states in the energy region scrE{≤}0.05 eV; elastic and symmetric charge-exchange cross sections for the same system were calculated without spin interactions for the scattering energies scrE{≤}4 eV. This energy region has been treated for the first time. The calculations have been done by the adiabatic method, where this three-body problem reduces to the multichannel-scattering problem. Very high scattering cross sections were obtained, expecially near the threshold for spin-flip processes.