2012/11/02 by S. Taj, B. Manaut, M. El Idrissi +1
Physics and Astronomy · #physics.atom-ph
published as CHINESE JOURNAL OF PHYSICS 49, 1164-1177, (2011) · 15 pages, 10 figures. arXiv admin note: substantial text overlap with arXiv:1211.0483; and text overlap with arXiv:physics/9911033 by other authors without attribution
arxiv created 2012/11/02 · arxiv updated 2012/12/09
The excitation of H (1s-2s) by electron impact in the presence and in the absence of the laser field is studied in the framework of the first Born approximation. The angular variation of the laser-assisted differential cross section (DCS) for atomic hydrogen by electronic impact is presented at various kinetic energies for the incident electron. The use of Darwin wave function as a semirelativistic state to represent the atomic hydrogen gives interesting results when the condition z/c≪1 is fulfilled. A comparison with the non relativistic theory and experimental data gives good agreement. It was observed that beyond (2700 eV) which represents the limit between the two approaches, the non relativistic theory does not yield close agreement with our theory and that, over certain ranges of energy, it can be in error by several orders of magnitude. The sum rule given by Bunkin and Fedorov and by Kroll and Watson \cite22 has been verified in both nonrelativistic and relativistic regimes.