Observation of structure in intermediate-energy positron-argon differential elastic scattering

Journal Article · Mon May 11 04:00:00 EDT 1992 · Physical Review Letters; (United States)

DOI:https://doi.org/10.1103/PhysRevLett.68.2913· OSTI ID:7043647

Dou, L; Kauppila, W E; Kwan, C K; Stein, T S ^[1]

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1. Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48202 (United States)

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{degree}, 90{degree}, and 120{degree} reveal an unexpected drop (a factor of 2 at 60{degree}) 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.

• OSTI ID: 7043647
• Journal Information: Physical Review Letters; (United States), Journal Name: Physical Review Letters; (United States) Vol. 68:19; ISSN PRLTA; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM COLLISIONS
COLLISIONS
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ELEMENTS
ENERGY RANGE
EV RANGE
EV RANGE 01-10
EV RANGE 10-100
EV RANGE 100-1000
EXPERIMENTAL DATA
FLUIDS
GASES
INFORMATION
MATRICES
NONMETALS
NUMERICAL DATA
POSITRON COLLISIONS
POSITRON-ATOM COLLISIONS
R MATRIX
RARE GASES
SCATTERING