Measurement of absolute elastic differential cross-sections for positron-methane scattering

Journal Article · Sat May 01 04:00:00 EDT 1993 · Bulletin of the American Physical Society

OSTI ID:281241

Przybyla, D A; Dou, L; Kwan, C K ^[1]

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1. and others

We have measured absolute elastic differential cross-sections (DCS`s) for positrons scattered from methane over the energy range 6 to 200 eV at scattering angles from 30 to 135 degrees. We use a crossed beam experiment to obtain the DCS for electron-methane scattering at 20 eV which is then normalized at 90 degrees to the absolute measurements of Tanaka et al. This normalization factor is used to obtain absolute positron DCS`s from our relative positron DCS measurements. Our absolute DCS`s are in qualitative agreement with the calculations of Jain and Gianturco. Because of the similarity in shape between the total cross-section curves for positron-methane and positron-argon scattering, it is of interest to determine whether a resonance-like structure seen in the elastic DCS for positron-argon scattering at intermediate energies also appears in the DCS for positron-methane scattering. No such structure has yet been found.

• OSTI ID: 281241
• Report Number(s): CONF-9305421--; CNN: Grant PHY-9021044
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 3 Vol. 38; ISSN 0003-0503; ISSN BAPSA6
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
METHANE
POSITRON-MOLECULE COLLISIONS