We have applied a distorted wave method to calculate the differential cross sections for 2 1S excitation of helium atom by electron impact in the energy range of 50-200 eV. The results are compared with some other ...

The Coulomb-projected Born method proposed by Geltman has been generalized by using the screened Coulomb potential of the form in place of the nuclear potential experienced by the incident electron. The results obtained ...

We have obtained differential and integral cross sections for the excitation of caesium atom to the lowest autoionizing level by positron impact using the distorted wave approximation. We have also done calculations for ...