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arXiv · 2303.02083

Many-Body Theory Calculations of Positron Scattering and Annihilation in H$_2$, N$_2$ and CH$_4$

C. M. Rawlins·J. Hofierka·B. Cunningham·C. H. Patterson·D. G. Green
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Abstract

The recently developed ab initio many-body theory of positron molecule binding [J. Hofierka et al., Nature, 606, 688 (2022)] is combined with the shifted pseudostates method [A. R. Swann and G. F. Gribakin, Phys. Rev. A 101, 022702 (2020)] to calculate positron scattering and annihilation rates on small molecules, namely H$_2$, N$_2$ and CH$_4$. The important effects of positron-molecule correlations are delineated. The method provides uniformly good results for annihilation rates on all the targets, from the simplest (H$_2$, for which only a sole previous calculation agrees with experiment), to larger targets, where high-quality calculations have not been available.

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C. M. Rawlins, J. Hofierka, B. Cunningham, C. H. Patterson, D. G. Green. 2023-03-03. Many-Body Theory Calculations of Positron Scattering and Annihilation in H$_2$, N$_2$ and CH$_4$. https://doi.org/10.1103/physrevlett.130.263001

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