Discriminating the heavy jet production mechanisms in associated Z + heavy flavor events at the LHC

We reconsider the associated Z boson and charm or beauty jet production at the LHC with paying special attention to the formation dynamics of heavy jets. Two different approaches are studied: first one, where heavy quarks are produced in the hard scattering subprocesses, implemented in the Monte-Carlo generator PEGASUS, and another scenario, where the hard scattering is calculated at NLO with MadGraph5_aMC@NLO and TMD parton shower is included (implemented in the Monte-Carlo generator CASCADE3). We compare the predictions obtained in both schemes with latest experimental data for associated Z+b production cross sections and the relative production rate σ(Z+c)/σ(Z+b) collected by the ATLAS and CMS Collaborations at $\sqrt{s}$=13 TeV. We introduce two kinematic observables (denoted as z${}_b$ and p${}_T^{rel}$) which can be used to discriminate the heavy jet production mechanisms. Using these variables we trace the shape of the simulated b-jet events and recommend that these observables be taken into consideration in the forthcoming experimental analyses.