An influence of the spectator-nuclear motion on nonresonant formation of the muonic hydrogen molecules

A model for description of nonresonant formation of the muonic molecules in collisions of the muonic hydrogen atoms with the hydrogenic molecules has been developed with taking into account the internal motion of all nuclei. It has been shown that such a motion leads to a significant smearing of the calculated energy-dependent formation rates at low collision energies. In particular, this effect is strong in the $dd\mu$ and $dt\mu$ formation. An appreciable isotopic effect in the case of nonresonant $dd\mu$ formation in $d\mu$ collisions with the molecules D$_2$ and HD has been found. All these effects are of importance for many experimental researches in low-energy muon physics.