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arXiv · 2402.13864

Measurement of energy correlators inside jets and determination of the strong coupling $\alpha_\mathrm{S}(m_\mathrm{Z})$

CMS Collaboration
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Abstract

Energy correlators that describe energy-weighted distances between two or three particles in a jet are measured using an event sample of $\sqrt{s}$ = 13 TeV proton-proton collisions collected by the CMS experiment and corresponding to an integrated luminosity of 36.3 fb$^{-1}$. The measured distributions are consistent with the trends in the simulation that reveal two key features of the strong interaction: confinement and asymptotic freedom. By comparing the ratio of the measured three- and two-particle energy correlator distributions with theoretical calculations that resum collinear emissions at approximate next-to-next-to-leading logarithmic accuracy matched to a next-to-leading order calculation, the strong coupling is determined at the Z boson mass: $\alpha_\mathrm{S}(m_\mathrm{Z})$ = 0.1229 $^{+0.0040}_{-0.0050}$, the most precise $\alpha_\mathrm{S}(m_\mathrm{Z})$ value obtained using jet substructure observables.

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CMS Collaboration. 2024-02-21. Measurement of energy correlators inside jets and determination of the strong coupling $\alpha_\mathrm{S}(m_\mathrm{Z})$. https://doi.org/10.1103/physrevlett.133.071903

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