Experimental total collision cross sections in the glory region for atom-molecule systems

In a crossed supersonic beam apparatus measurements have been performed on the total cross section as a function of velocity in the thermal range for the systems O2-Ar; O2-Kr; N2-Ar and NO-Ar. The anisotropy of the interaction effects the glory structure in the total cross section through a shift in the position of the glories and a quenching of the amplitudes. The analysis of the data is performed within the framework of the infinite order sudden approximation. An analytical expression for the shift function and the quenching function is derived. Assuming a P2-type anisotropy in the potential the value of the effective anisotropy parameter is determined together with the earlier introduced quantities related to the spherical part of the potentials. The various potentials proposed in the literature for the presently investigated systems are tested accordingly.