PARAMETRIZATION OF LOW-ENERGY SYMMETRICAL (E,2E) DIFFERENTIAL CROSS-SECTION MEASUREMENTS

Symmetric (e, 2e) experimental studies on helium over a very wide rang e of scattering geometries at energies from 1 to 50 eV above the ioniz ation threshold are parametrized in terms of a set of universal irredu cible tensorial angular functions. Measurements from the Manchester an d Paris experimental groups are used in this parametrization, which pr ovides a complete picture of the symmetric ionization process. The use of the parametrization technique for deconvolution of the experimenta l angular resolution from measured results is discussed.