  The consequences of application of new set of criteria, proposed in our
previous works, for the improvement of a jet energy calibration accuracy with
the process "p~p->photon+jet+X" at Tevatron and for a reduction of background
events contribution are studied. The efficiencies of the used selection
criteria are estimated. The distributions of these events over photon Pt and
jet pseudorapidity are presented. The features of "photon+jet" events in the
central calorimeter region of the D0 detector (|\eta|<0.7) are investigated. It
is also shown that the samples of "photon+jet" events, selected with the cuts
used for the jet energy calibration, may have the statistics sufficient for
determining the gluon distribution function of a proton in the region of
2*10^{-3}< x < 1.0 and the values of Q^2 by one order higher than that reached
in the experiments at HERA. Monte Carlo events produced by the PYTHIA 5.7
generator are used for this aim.
