Angular decorrelations in $\gamma + 2 jet$ events at high energies in the parton Reggeization approach

We discuss associated production of prompt photon plus two jets at high energies in the framework of the parton Reggeization approach, which is based on multi-Regge factorization of hard processes and Lipatov's effective theory of Reggeized gluons and quarks. In this approach, initial-state off-shell effects and transverse momenta of initial partons are included in a gauge-invariant way. We compute transverse momentum spectra of prompt photons in inclusive $\gamma-$production, in $\gamma + jet$ and $\gamma+2jets$ events, and azimuthal angle difference spectrum in $\gamma + 2 jet$ events. We compare our results with the experimental data from D0 Collaboration at Tevatron and with the theoretical predictions obtained in conventional NLO approximation of the collinear parton model. The relation between SPS and DPS production mechanisms is also studied.