$\gamma^* \gamma^*$ reactions at high energies

A. Donnachie, H.G. Dosch, M. Rueter
2000 European Physical Journal C: Particles and Fields  
The total hadronic gamma*gamma* cross sections at high energy are calculated as a function of energy and photon virtuality in a model combining Regge exchange, the quark box diagram (a fixed pole in Regge language) and soft and hard pomeron exchanges evaluated in the context of dipole-dipole scattering. Good agreement is obtained with the data for the real gamma-gamma cross section and for the real photon structure function. However the model prediction for the gamma* gamma* cross section is
more » ... cross section is too small. This is attributed to an incorrect extrapolation of the Q^2 dependence of the hard pomeron adopted here. Parametrising it independently shows that the hard part of the cross section can be well represented by a simple Regge pole with intercept ~ 1.3.
doi:10.1007/s100520000268 fatcat:cyysqtoetjgy3h4wzgjle43cka