Eur. Phys. J. D 63, 327-337 (2011)
https://doi.org/10.1140/epjd/e2011-10570-1

Regular Article

Multiple series of shape resonances and near-zero-energy cross section enhancements in photoionization of hydrogen-like ions with screened coulomb interaction

¹ School of Mathematics & Physics and information engineering, Jiaxing University, Jiaxing 314001, P.R. China
² Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, P.O. Box 8009-26, Beijing 100088, P.R. China
³ Macedonian Academy of Sciences and Arts, P.O. Box, 428, 1000 Skopje, Macedonia

^a e-mail: qiyying@yahoo.com.cn

Received: 8 October 2010
Received in final form: 1 April 2011
Published online: 28 June 2011

Abstract

The recently discovered multiple series of shape resonances and near-zero-energy enhancements in photoionization cross section of hydrogen-like atomic systems with screened Coulomb (Yukawa type) interaction [Phys. Rev. A 80, 063404 (2009)] are studied in detail, in particular their evolution with the variation of the screening strength of the potential. The conditions for appearance of these multiple series of cross section features are identified and related to certain critical screening strengths of the potential. A relation between the appearance of Cooper minima and shape resonaces in the photoionizations cross section has been established. It is also shown that the s-channel of np photoionization for a fixed photoelectron energy exhibits Ramsauer-Townsend minima in the screening length variable.