Epithermal muonium processes in methane and propane gases. [Mev muons]

Journal Article · Thu Sep 19 04:00:00 EDT 1991 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100172a043· OSTI ID:5198904

Kempton, J R; Arseneau, D J; Fleming, D G; Senba, M; Gonzalez, A C; Pan, J J; Tempelmann, A; Garner, D M ^[1]

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1. Univ. of British Columbia, Vancouver (Canada)

Gas-phase {mu}SR studies of dense methane up to 10 mol L{sup {minus}1} and of propane at low densities, up to 0.2 mol L{sup {minus}1}, are reported. It is found that the diamagnetic polarization, P{sub D}, increases in both gases with pressure, with a related decrease seen in the muonium polarization, P{sub Mu}. The initial increase seen in P{sub D} at low densities is attributed to hot-atom (Mu*) abstraction and substitution reactions. Comparisons with both hot-tritium (T*) and epithermal H* reactions in the alkanes reveal substantial isotope effects. In the case of CH{sub 4}, a continued increase in P{sub D} at higher densities is likely due to a proton-transfer reaction from the molecular ion CH{sub 4}Mu{sup +} in the radiolysis track, forming CH{sub 3}Mu, rather than to hot-atom reactions. Extrapolation of the present trend with density gives agreement with the value of P{sub D} found in liquid CH{sub 4}, indicating that the diamagnetic muon polarization in dense alkanes depends primarily on density rather than on temperature or phase.

• OSTI ID: 5198904
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 95:19; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700411* -- Inertial Confinement Devices-- (1992-)
ALKANES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CATIONS
CHARGED PARTICLES
CHARGED-PARTICLE TRANSPORT
CHEMICAL REACTIONS
CHEMISTRY
COLLISIONS
DENSITY
DIAMAGNETISM
ELEMENTS
HOT ATOM CHEMISTRY
HYDROCARBONS
HYDROGEN
HYDROGEN ISOTOPES
IONS
ISOTOPE EFFECTS
ISOTOPES
LIGHT NUCLEI
MAGNETISM
MATHEMATICAL MODELS
METHANE
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
POLARIZATION
PROPANE
PROTON TRANSPORT
RADIATION TRANSPORT
RADIOCHEMISTRY
RADIOISOTOPES
TRITIUM
YEARS LIVING RADIOISOTOPES