Double Parton Scatterings in High-Energy Proton-Nucleus Collisions and Partonic Correlations

The joint study of Double Parton Scatterings, in high energy proton-proton and proton-nucleus collisions, can provide a lot of information on multi-parton correlations. The multi-parton structure is in fact probed in a different way by DPS, in $p$-$p$ and in $p$-$A$ collisions. In $p$-$A$ collisions the interpretation of the experimental results may be however complicated by the presence of interference terms, which are missing in $p$-$p$. A suitable reaction channel, where interference terms are absent, is $WJJ$ production. By studying $WJJ$ production in $p$-$Pb$ collisions, we estimate that the fraction of events due to DPS may be larger by a factor 3 or 4, as compared to $p$-$p$, while the amount of the increased fraction can give a direct indication on the importance of different correlation terms.