Journal ArticleDOI
Evidence for absorption effects in positron elastic scattering by argon.
TLDR
These measurements provide strong evidence that the positronium formation channel is having a significant absorption effect on the elastic-scattering channel, as is observed by the washing out of clear structure present in the measured elastic differential cross section below 9.0 eV.Abstract:
Relative differential cross sections for elastic scattering of 5--50-eV positrons by argon atoms at angles from 30{degree} to 134{degree} are measured in a crossed-beam experiment. These measurements provide strong evidence that the positronium formation channel (threshold=9.0 eV) is having a significant absorption'' effect on the elastic-scattering channel, as is observed by the washing out'' of clear structure (a maximum and minimum) present in the measured elastic differential cross section below 9.0 eV (where good agreement is found with theory) when the positron energy is increased to higher energies.read more
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Journal ArticleDOI
Recent advances in the comparison of matter- and antimatter-atom collisions
TL;DR: In this paper, the authors review the developments with particular emphasis on the processes of ionization and charge transfer, focusing on low energy antimatter projectiles and their effect on the dynamics of ion-atom collisions.
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Threshold and channel-coupling effects in positron elastic scattering from noble gases
W. E. Meyerhof,G. Laricchia +1 more
TL;DR: In this article, the authors examined angular-distribution measurements of positrons elastically scattered from noble-gas targets at energies near the positronium (Ps) threshold and found evidence for the dominance of channel coupling near the Ps threshold between the (incoming, outgoing) orbital angular momentum channels (1,0) and (2,1), respectively.
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The effect of positronium formation on close-coupling calculations of positron-lithium collisions
TL;DR: In this article, the lithium atom was described within a single-electron approximation using a model potential, and the effect upon excitation and elastic scattering due to the coupling of positronium formation channels was investigated.
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Positron-molecule scattering experiments
TL;DR: In this paper, the relative elastic differential cross sections (DCSs) and positronium formation cross sections for positron scattering were extended to include molecules of varying complexity and symmetry.
Journal ArticleDOI
Positron - argon elastic, positronium formation and ionizing collisions at
TL;DR: In this article, the energy dependencies of the differential cross sections for elastic scattering, positronium formation and direct single ionization in positron - argon collisions at are reported in the energy range 40 - 150 eV.