Rotational excitations in muonic atom scattering by molecular hydrogen

A computational scheme based on the infinite order sudden approximation (IO S) is proposed for treating molecular and screening effects in muonic atom scattering at low energies. With this scheme the differential (d sigma/d Om ega) (epsilon, j <-- 0\theta) and the total sigma(tot)(epsilon) cross-secti ons of muonic atom scattering on molecules of hydrogen isotopes are calcula ted at energies epsilon(rot)= (h) over bar omega(I) less than or equal to e psilon less than or equal to epsilon(vib) = (h) over bar omega(nu). The IOS permits a quantitative analysis of the dependence of the differential cros s-sections on the scattering angle and on the rotational excitations, parti cularly the rotational rainbow effects. An attractive feature of this appro ach is also to include the energy and the angular dependencies in the "inpu t" cross-sections describing the muonic atom scattering on each bare nucleu s of the molecule. The calculated total cross-sections sigma(tot)(epsilon) are in agreement with the data obtained earlier with the pseudopotential ap proach.