Low-energy electron-helium scattering in a Nd-YAG laser field

We study the electron-impact excitation of atomic helium, in the presence of a linearly polarized Nd-YAG laser field, accompanied by the transfer of l photons, for low collision energy of 25 eV and laser intensity of 5.3 x 10(11) W cm(-2). The second-order Born approximation has been used to calculate the differential cross sections. Detailed calculations of the scattering amplitudes are performed by using the Sturmian basis expansion. A detailed analysis is made of the excitation of the 1(1)S -> 2(1)S and 1(1)S -> 2(1)P transitions. We discuss the behavior and the variation of the cross sections corresponding to the excitation process for various geometrical configurations. (C) 2014 Elsevier B.V. All rights reserved.