Samples of inclusive $\gamma +2$ jet and $\gamma +3$ jet events collected by the D0 experiment with an integrated luminosity of about $1{\mathrm{fb}}^{-1}$ in $p\overline{p}$ collisions at $\sqrt{s}=1.96\mathrm{TeV}$ are used to measure cross sections as a function of the angle in the plane transverse to the beam direction between the transverse momentum ($p_T$) of the $\gamma +\mathrm{\text{leading jet system}}$ (jets are ordered in $p_T$) and $p_T$ of the other jet for $\gamma +2$ jet, or $p_T$ sum of the two other jets for $\gamma +3$ jet events. The results are compared to different models of multiple parton interactions (MPI) in the pythia and sherpa Monte Carlo (MC) generators. The data indicate a contribution from events with double parton (DP) interactions and are well-described by predictions provided by the pythia MPI models with $p_T$-ordered showers and by sherpa with the default MPI model. The $\gamma +2$ jet data are also used to determine the fraction of events with DP interactions as a function of the azimuthal angle and as a function of the second jet $p_T$.

• Received 10 January 2011

DOI:https://doi.org/10.1103/PhysRevD.83.052008