Kinetic processes of muonium formation by non-thermalized electrons in the spur model

An approximate analytical solution is obtained for the kinetic equation for electrons in the field of a Coulomb centre formed by a muon in the end of its track. It is shown that thermalization times and could differ by several orders of magnitude, depending on the behaviour of transport cross sections. The fraction of non-thermalized electrons returning to the muon and forming muonium (P Mu ) depends on pressure and temperature. Therefore,μSR experiments give us an opportunity to obtain information on the distribution function of track electrons.