We examine present data for double parton scattering at LHC and discuss their energy dependence from its earliest measurements at the ISR. Different models for the effective cross-section are considered and their behavior studied for a variety of selected final states. We point out that data for pp ->4 jets or pp -> quarkonium pair indicate the effective cross-section to increase with energy. We compare this set of data with different models, including one inspired by our soft gluon resummation model for the impact parameter distribution of partons.
The experimental capability of recognizing the presence of b quarks in complex hadronic final states has addressed the attention towards final states with bbar{b} pairs for observing the production of the Higgs boson at the LHC, in the intermediate Higgs mass range.We point out that double parton scattering processes are going to represent a sizeable background to the process.
We present predictions for the double parton scattering (DPS) four-jet production cross sections in $pA$ collisions at the LHC. Relying on the experimental capabilities to correlate centrality with impact parameter $B$ of the proton-nucleus collision, we discuss a strategy to extract the double parton scattering contributions in $pA$ collisions, which gives direct access to double parton distribution in the nucleon. We show that the production cross sections via DPS of four jets, out of which two may be light- or heavy-quark jets, are large enough to allow the method to be used already with data accumulated in 2016 $pA$ run.
We present results on Zjj production via double parton scattering in pA collisions at the LHC. We perform the analysis at leading and next-leading order accuracy with different sets of cuts on jet transverse momenta and accounting for the single parton scattering background. By exploiting the experimental capability to measure the centrality dependence of the cross section, we discuss the feasibility of DPS observation in already collected data at the LHC and in future runs.
Double parton scattering (DPS) is studied at the example of $J/psi$ pair-production in the LHCb and ATLAS experiments of the Large Hadron Collider (LHC) at centre-of-mass energies of $sqrt{S}=$ 7, 8, and 13 TeV. We report theoretical predictions delivered to the LHCb and ATLAS collaborations adjusted for the fiducial volumes of the corresponding measurements during Run I and provide new predictions at 13 TeV collision energy. It is shown that DPS can lead to noticeable contributions in the distributions of longitudinal variables of the di-$J/psi$ system, especially at 13 TeV. The increased DPS rate in double $J/psi$ production at high energies will open up more possibilities for the separation of single parton scattering (SPS) and DPS contributions in future studies.
By working out the kinematics of double parton scattering at short relative transverse distances, we obtain an explicit link between the transverse centres of mass, of the two hard partonic interactions, and the contributions to the process, due to pairs of interacting partons generated by perturbative splitting. One my thus foresee the interesting possibility of discriminating experimentally between contributions to the double parton scattering cross section, due to interacting parton pairs originated by independent evolution, and contributions, due to interacting parton pairs generated by splitting.