Muonium rate constants

Other research in tire area of addition reactions onto unsaturated carbon-carbon bonds has included measurement of the rate coefficients for tire addition of NO3 to chloro- and trichloro-ethene,147 relative rate measurement for N03 addition to isoprene,148 TF-/(SR-measured muonium addition to vinyl aromatics12 and EPR studied addition of radical (65) to alkenes.150 In this latter study a linear dependence of the rate constant of addition with tire donor/acceptor properties of the alkene partner was highlighted. 

Muonium has been observed in pure hydrocarbons ( ), alcohols (, 7 ), and water ( ). Because Mu reacts slowly with these pure liquids, giving observable reaction lifetimes of Mu up to 4us, they can be used as solvents to study various solutes of interest. As the free triplet Mu atom reacts with the solute its observed precession frequency is damped and a decay constant, X can be obtained. The concentration dependence of the decay constant provides second order chemical rate constants for Mu addition, abstraction, spin conversion, and oxidation-reduction reactions. When analogous hydrogen atom rate constants are available the kinetic isotope effect can also be calculated. 

Muonium is useful as a hydrogen-like probe to study the atomic and radical reactions of hydrogen because Mu s reaction decay constant is directly observable, while most hydrogen atom data come from measured relative rate constants. The more we know of the reactions of hydrogen, the simplest and most abundant element in the universe, the sooner we will be better able to understand more complex atoms and their reactions. 

It is the interplay between particle physics and QED phenomena in the muonium atom which cause increasing understanding of fundamental forces and increasing reliability of extracted fundamental constants. None of both sides could reach significant results without the other. With the significant improvement expected for muon beam rates at various places we can look forward to further insights and maybe hints why there are particle generations. 

Calculations show that the fraction of muonium formed as a function of the energy of the incident beam increases as the available rate of muons decreases. The absolute number of muonium atoms formed is nearly constant. Hence to go to very low momentum (7-lOMeV/c) increases the relative fraction of muonium atoms formed and decreases background. The stopped muon channel at LAMPF can be tuned down to less than 3MeV/c but at less than 5MeV/c the... 

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