Observation of structure in intermediate-energy positron-argon differential elastic scattering
- 11 May 1992
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 68 (19) , 2913-2916
- https://doi.org/10.1103/physrevlett.68.2913
Abstract
We report the first direct observation of a resonancelike structure for positron scattering by an atom or molecule. Our initial absolute elastic differential cross-section measurements for positron scattering by argon when plotted versus energy (8.7 to 300 eV) at fixed scattering angles of 60°, 90°, and 120° reveal an unexpected drop (a factor of 2 at 60°) between 55 and 60 eV. This structure is puzzling because it does not occur near any known inelastic threshold energy and may relate to a cross-channel coupling effect with an open inelastic-scattering channel.Keywords
This publication has 23 references indexed in Scilit:
- Positron scattering by atomic hydrogen including positronium formationJournal of Physics B: Atomic, Molecular and Optical Physics, 1991
- Search for resonances in positron-atom systemsPhysical Review A, 1990
- P-wave resonances in positron-hydrogen scatteringJournal of Physics B: Atomic, Molecular and Optical Physics, 1990
- Evidence for absorption effects in positron elastic scattering by argonPhysical Review Letters, 1990
- Bound states of positrons and large moleculesPhysical Review Letters, 1988
- Positron Differential Elastic-Scattering Cross-Section Measurements for ArgonPhysical Review Letters, 1986
- Positronium—its Formation and Interaction with Simple SystemsPublished by Elsevier ,1986
- The method of complex coordinate rotation and its applications to atomic collision processesPhysics Reports, 1983
- Optical model theory of elastic electron- and positron-argon scattering at intermediate energiesJournal of Physics B: Atomic and Molecular Physics, 1977
- The scattering of electrons from inert gases. I. Absolute differential elastic cross sections for argon atomsJournal of Physics B: Atomic and Molecular Physics, 1975