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arXiv · 1808.07340

Measurement of jet substructure observables in $\mathrm{t\overline{t}}$ events from proton-proton collisions at $\sqrt{s} =$ 13TeV

CMS Collaboration
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Abstract

A measurement of jet substructure observables is presented using $\mathrm{t\overline{t}}$ events in the lepton+jets channel from proton-proton collisions at $\sqrt{s} =$ 13 TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Multiple jet substructure observables are measured for jets identified as bottom, light-quark, and gluon jets, as well as for inclusive jets (no flavor information). The results are unfolded to the particle level and compared to next-to-leading-order predictions from POWHEG interfaced with the parton shower generators PYTHIA 8 and HERWIG 7, as well as from SHERPA 2 and DIRE 2. A value of the strong coupling at the Z boson mass, $α_S(m_\mathrm{Z}) = $ 0.115 $^{+0.015}_{-0.013}$, is extracted from the substructure data at leading-order plus leading-log accuracy.

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CMS Collaboration. 2018-12-02. Measurement of jet substructure observables in $\mathrm{t\overline{t}}$ events from proton-proton collisions at $\sqrt{s} =$ 13TeV. https://doi.org/10.1103/physrevd.98.092014

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