Associated Higgs + jet(s) production at the LHC and CCFM gluon dynamics in a proton

Abstract

We consider the associated production of Higgs boson and hadronic jet(s) in $pp$ collisions at the LHC for the first time using the $k_T$-factorization approach. Our analysis is based on the off-shell gluon-gluon fusion subprocess, where non-zero transverse momenta of initial gluons are taken into account and covers $H\to \gamma \gamma$, $H\to Z{Z}^{\ast }\to 4l$ (with $l=e,\mu$) and $H\to W^{+}{W}^{-}\to e^{\pm }{\mu }^{\mp }\nu \bar{\nu }$ decay channels. The transverse momentum dependent (TMD) gluon densities in a proton are taken from Catani-Ciafaloni-Fiorani-Marchesini evolution equation. To simulate the kinematics of the produced jets the TMD parton shower implemented into the Monte-Carlo event generator \textsc{cascade} is applied. The comparison of our results with the latest experimental data taken by the CMS and ATLAS Collaborations at $\sqrt{s}=8$ and $13$ TeV and conventional higher-order perturbative QCD calculations is presented. We highlight observables, which are sensitive to the TMD gluon densities in a proton.

Comments: 14 pages, 6 figures