Consequences of conical intersections in the H+O-2->OH+O reaction?

Doppler-resolved laser-induced fluorescence spectroscopy of the OH reaction products of the photoinitiated reaction H + O-2 --> OH + O has been applied at collision energies near 1.8 eV, where an anomalous peak in the total reaction cross section has been reported by Kessler and Kleinermanns (J. Chem. Phys. 1992, 97, 374). Although the product state distributions show no remarkable variation as the collision energy varies through this region, analysis of the Doppler line shapes suggests a sideways scattering component to the differential cross sections near 1.8 eV that is not present at higher collision energies. We propose that the qualitative change in the differential cross sections as well as the local peak in the integral cross section can be a consequence of the dynamics in the vicinity of the C-2 upsilon conical intersection.