Velocity dependence of ionization and fragmentation of methane caused by fast-proton impact

Journal Article · Tue Feb 01 04:00:00 EST 1994 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.49.881· OSTI ID:5259127

Ben-Itzhak, I; Carnes, K D; Johnson, D T; Norris, P J; Weaver, O L ^[1]

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1. James R. Macdonald Laboratory, Department of Physics, Kansas State Univeristy, Manhattan, Kansas 66506 (United States)

The velocity dependence of methane ionization and fragmentation have been studied using a coincidence time-of-flight technique. The relative yields of single-ion, ion-pair, and ion-triple channels have been determined for 1- to 12-MeV proton impact. The multiple-ionization cross sections have been determined and are in accord with our model semiclassical Coulomb approximation calculations. The single-ion channels resulting from the breakup of CH[sub 4][sup +*] were found to be independent of the collision velocity. Good agreement with previous proton-impact measurements and with electron-impact measurements is observed. On the other hand, the ion-pair breakup channels of CH[sub 4][sup 2+*] show a surprising dependence on the collision velocity. The ion-pair data are in reasonable agreement with fast-electron-impact measurements at 10 keV while differing significantly with a lower, 1-keV, electron-impact measurement.

• OSTI ID: 5259127
• Journal Information: Physical Review A; (United States), Journal Name: Physical Review A; (United States) Vol. 49:2; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

664300* -- Atomic & Molecular Physics-- Collision Phenomena-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ALKANES
BARYONS
COINCIDENCE METHODS
COLLISIONS
CORRELATIONS
COUNTING TECHNIQUES
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
HADRONS
HYDROCARBONS
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONIZATION
METHANE
MEV RANGE
MEV RANGE 01-10
MEV RANGE 10-100
MOLECULE COLLISIONS
NUCLEONS
ORGANIC COMPOUNDS
PROTONS
TIME-OF-FLIGHT METHOD
VELOCITY
YIELDS