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Main diagrams corresponding to the hadron production in \gaga interactions via vector meson interactions (VDM-like, a), point-like interactions (QPM-like, b)and with one (c) or both (d) photons resolved into partons.

\xplmi-space divided by $x_{\gamma}$ into four domains(`Dir', `SR' and `DR' notations are introduced in section 3.

Comparison of the total energy outside the reconstructed jets $E_{out}$ with the simulation for the selected data (a), and data in the phase-space domains `Dir' (b), `SR' (c) and `DR' (d), described in section 3 of the text. The thick solid histograms correspond to the sum of the di-jet \gaga interactions as predicted by PYTHIA and the background processes. The contributions of different \gaga subprocesses are shown by dotted (QPM term),dashed-dotted (single-resolved) and thin solid (double-resolved) histograms.

Comparison of the background subtracted data with the simulation after the fit for the charged multiplicity (a), the invariant mass calculated with the charged particles only (b), ($x^+_\gamma+x^-_\gamma$)/2 (c) and the mean number of particles in the reconstructed jets (d). The simulation (thick solid histograms) sums all three model components scaled with the factors given in the text. The contributions of \gaga subprocesses are shown by dotted (QPM term),dashed-dotted (single-resolved) and thin solid (double-resolved) histograms.

Hadronisation corrections as a function of the mean jet transverse momentum \ptmean (a) and the absolute differenceof jet rapidities $|\Delta\eta|$ (b).

Hadronisation corrections as a function of the mean jet transverse momentum \ptmean (a) and the absolute differenceof jet rapidities $|\Delta\eta|$ (b).

Detector efficiency as a function of \ptmean (a) and$|\Delta\eta|$ (b).

Detector efficiency as a function of \ptmean (a) and$|\Delta\eta|$ (b).

Distributions of the mean jet transverse momentum \ptmean (a) and the absolute difference of jet rapidities $|\Delta\eta|$ (b). The data are presented by bars, the sum of the scaled PYTHIA prediction and of the background by solid histograms. The background components are shown by dash-dotted lines (MIA contribution), by dashed lines (`non2-to-2 jets' background)and by shaded histograms (`non-$\gamma\gamma$' background).

Distributions of the mean jet transverse momentum \ptmean (a) and the absolute difference of jet rapidities $|\Delta\eta|$ (b). The data are presented by bars, the sum of the scaled PYTHIA prediction and of the background by solid histograms. The background components are shown by dash-dotted lines (MIA contribution), by dashed lines (`non2-to-2 jets' background)and by shaded histograms (`non-$\gamma\gamma$' background).

Cross-section of di-jet production in quasi-real \agg interactions as a function of \ptmean (a) and $|\Delta\eta|$ (b). The jets are reconstructed by the \kt within the pseudo-rapidity range of $-1<\eta<1$ and the jet transverse momentum $p_T$ above 3 GeV/c. Dashed histograms show the leading order calculations andnext-to-leading order calculations \cite{theor} are presented by open diamonds.

Cross-section of di-jet production in quasi-real \agg interactions as a function of \ptmean (a) and $|\Delta\eta|$ (b). The jets are reconstructed by the \kt within the pseudo-rapidity range of $-1<\eta<1$ and the jet transverse momentum $p_T$ above 3 GeV/c. Dashed histograms show the leading order calculations andnext-to-leading order calculations \cite{theor} are presented by open diamonds.

Cross-section of the `direct' term as a function of \ptmean (a) and $|\Delta\eta|$ (b). Dashed histograms correspond to the PYTHIA predictions scaled according to the fit.The circles (squares) present the results of the NLO (LO) calculations \cite{theor}.

Cross-section of the `direct' term as a function of \ptmean (a) and $|\Delta\eta|$ (b). Dashed histograms correspond to the PYTHIA predictions scaled according to the fit.The circles (squares) present the results of the NLO (LO) calculations \cite{theor}.