Four-jet production in single- and double-parton scattering within high-energy factorization

TL;DR

This study explores four-jet production at the LHC using high-energy factorization, comparing single- and double-parton scattering contributions and contrasting results with collinear factorization, highlighting the importance of kinematic effects.

Contribution

It provides the first comprehensive analysis of 4-jet production within the high-energy factorization framework, including both SPS and DPS contributions and their comparison to collinear approaches.

Findings

HEF results for DPS are smaller than collinear results with symmetric cuts.

Kinematic effects explain differences between HEF and collinear results.

HEF better describes angular correlations among jets.

Abstract

We perform a first study of 4-jet production in a complete high-energy factorization (HEF) framework. We include and discuss contributions from both single-parton scattering (SPS) and double-parton scattering (DPS). The calculations are performed for kinematical situations relevant for two experimental measurements (ATLAS and CMS) at the LHC. We compare our results to those reported by the ATLAS and CMS collaborations for different sets of kinematical cuts. The results of the HEF approach are compared with their counterparts for collinear factorization. For symmetric cuts the DPS HEF result is considerably smaller than the one obtained with collinear factorization. The mechanism leading to this difference is of kinematical nature. We conclude that an analysis of inclusive 4-jet production with asymmetric $p_T$-cuts below 50 GeV would be useful to enhance the DPS contribution relative to the SPS contribution. In contrast to the collinear approach, the HEF approach nicely describes the distribution of the $\Delta S$ variable, which involves all four jets and their angular correlations.