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arXiv · 2111.04521

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

Abstract

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 $\sigma(Z + c)/\sigma(Z + b)$ collected by the ATLAS and CMS Collaborations at $\sqrt s = 13$~TeV. We introduce two kinematic observables (denoted as $z_b$ and $p_T^{\rm rel}$) 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.

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S. P. Baranov, A. Bermudez Martinez, H. Jung, A. V. Lipatov, M. A. Malyshev, S. Taheri Monfared. 2021-11-08. Discriminating the heavy jet production mechanisms in associated $Z$ + heavy flavor events at the LHC. https://doi.org/10.1140/epjc%2Fs10052-022-10104-7

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