Ionization of the molecular targets using the coherent and incoherent ion beams

Document Type : Full length research Paper

Author

Department of Physics, Faculty of Sciences, University of Isfahan, Isfahan 81746-73441, Iran

Abstract

One of the important and interesting aspects of the ionization of the molecular targets using the ionic beams is the interference which occurs between the beams scattered from different molecular scattering centers. Experience has shown that the interference patterns occurred using the coherent and incoherent beams have some small but important differences with each other. The taking into account of the origin of these differences by theoretical approaches is usually difficult even impossible. In this research, a theoretical model is proposed to study the triple differential cross sections of ionization of hydrogen molecules by coherent projectile beams. In this model, the ionization cross section is obtained by a superposition of the partial cross sections in the two-effective-center (TEC) approximation with one and two Coulomb waves. The obtained results for collision of protons with hydrogen molecules are compared with experimental data. Comparison shows that the interference effects due to the superposition of the two partial amplitudes are in good agreement with the interference patterns observed for the coherent proton beam.

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