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arXiv · 1812.04095

Measurement of the energy density as a function of pseudorapidity in proton-proton collisions at $\sqrt{s} =$ 13 TeV

CMS Collaboration
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Abstract

A measurement of the energy density in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} =$ 13 TeV is presented. The data have been recorded with the CMS experiment at the LHC during low luminosity operations in 2015. The energy density is studied as a function of pseudorapidity in the ranges $-$6.6 $< \eta$ $< -$5.2 and 3.15 $< |\eta| <$ 5.20. The results are compared with the predictions of several models. All the models considered suggest a different shape of the pseudorapidity dependence compared to that observed in the data. A comparison with LHC proton-proton collision data at $\sqrt{s} =$ 0.9 and 7 TeV confirms the compatibility of the data with the hypothesis of limiting fragmentation.

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CMS Collaboration. 2018-12-10. Measurement of the energy density as a function of pseudorapidity in proton-proton collisions at $\sqrt{s} =$ 13 TeV. https://doi.org/10.1140/epjc%2Fs10052-019-6861-x

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