Positron-atom scattering using pseudostate energy shifts

被引:29
作者
Mitroy, J. [1 ]
Zhang, J. Y. [1 ]
Bromley, M. W. J. [2 ,3 ]
Young, S. I. [2 ,3 ]
机构
[1] Charles Darwin Univ, Fac Technol, ARC Ctr Anti Matter Studies, Darwin, NT 0909, Australia
[2] San Diego State Univ, Dept Phys, San Diego, CA 92182 USA
[3] San Diego State Univ, Res Ctr Comp Sci, San Diego, CA 92182 USA
来源
PHYSICAL REVIEW A | 2008年 / 78卷 / 01期
关键词
D O I
10.1103/PhysRevA.78.012715
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
A method to generate low-energy phase shifts for elastic scattering using bound-state calculations is applied to the problem of e(+)-Mg and e(+)-Zn scattering after an initial validation on the e(+)-Cu system. The energy shift between a small reference calculation and the largest possible configuration interaction calculation of the lowest-energy pseudostate is used to tune a semiempirical optical potential. The potential was further fine-tuned by utilizing the energy of the second lowest pseudostate. The s- and p-wave phase shifts for positron scattering from Mg and Zn are given from threshold to the first excitation threshold. The e(+)-Mg cross section has a prominent p-wave shape resonance at an energy of about 0.096 eV with a width of 0.106 eV. The peak cross section for e(+)-Mg scattering is about 4800a(0)(2), while Z(eff) achieves a value of 1310 at an energy of 0.109 eV.
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页数:13
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