Positron elastic scattering from alkaline earth targets

• Published in: The European physical journal. D, Atomic, molecular, and optical physics Vol. 70; no. 7
• Main Authors: Poveda, Luis A., Assafrão, Denise, Mohallem, José R.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2016
• Subjects: Applications of Nonlinear Dynamics and Chaos Theory; Atomic; Molecular; Optical and Plasma Physics; Physical Chemistry; Physics; Physics and Astronomy; Quantum Information Technology; Quantum Physics; Regular Article; Spectroscopy/Spectrometry; Spintronics; Topical Issue: Advances in Positron and Electron Scattering
• ISSN: 1434-6060; 1434-6079
• DOI: 10.1140/epjd/e2016-70120-y

A previously reported model potential approach [Poveda et al., Phys. Rev. A 87 , 052702 (2013)] was extended to study low energy positron elastic scattering from beryllium and magnesium. The cross sections were computed for energies ranging from 10 -5 eV up to well above the positronium formation threshold. The present results are in good agreement with previous reports, including the prediction of a p -wave resonance in the cross section for magnesium. The emergence of this shape resonance is connected to a trend observed in the evolution of the partial wave cross section in going from Be to Mg target. This trend lead us to speculate that a sharp d -wave resonance should be observed in positron elastic scattering from calcium. The positron-target binding energies are investigated in detail, both using the scattering information and by direct computation of the bound state energies using the model potentials. Graphical abstract