Heavy quark pair correlations in QCD

The azimuthal correlations of heavy quarks produced in high energy pp () collisions are calculated in the perturbative QCD without usual assumptions of the parton model. The virtual nature of the interacting gluons as well as their transverse motion and different polarizations are taken into account within the framework of the semihard processes theory describing the parton distributions in the region of the small Bjorken variable x. We give some predictions for the azimuthal correlations of charm and beauty hadrons produced at Tevatron-collider and LHC. Our approach can be of interest also for HERA energy region, since it shows a difference with the conventional parton model in the small x domain.