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arXiv · 2011.08016

Atomic ionization by multicharged ions interpreted in terms of poles in the velocity complex space

J. E. Miraglia
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Abstract

We study the single ionization of hydrogen and helium by the impact of a highly-charged Coulomb projectile. To interpretate the cross section we introduce a diagonal Pad\'{e} approximant. We find that the use of Pad\'{e}% [4,4] describes very well the Continnum Distorted Wave Eikonal Initial State theory within its range of validity. The nodes of the denominator of the Pad% \'{e} approximant give rise to four poles in the velocity complex plane: two in the upper plane and their conjugate in the lower plane. The dependence of these poles with the projectile charge can be reasonably fitted to give a closed-form for the ionization cross section, resulting a scaling very near to the one of Janev and Presnyakov. The experiments available were described very well in its entire velocity range with the use of a Pad\'{e}[8,8], having four poles in the upper plane and their conjugate in the lower plane. We conclude that the poles of the Pad\'{e} approximant seem to have all the information of the total ionization cross section

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J. E. Miraglia. 2020-11-16. Atomic ionization by multicharged ions interpreted in terms of poles in the velocity complex space. https://doi.org/10.1088/1361-6455/abf01b

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