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arXiv · 1507.05915

Pseudorapidity distribution of charged hadrons in proton-proton collisions at sqrt(s) = 13 TeV

CMS Collaboration
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Abstract

The pseudorapidity distribution of charged hadrons in pp collisions at sqrt(s) =13 TeV is measured using a data sample obtained with the CMS detector, operated at zero magnetic field, at the CERN LHC. The yield of primary charged long-lived hadrons produced in inelastic pp collisions is determined in the central region of the CMS pixel detector (abs(eta)<2) using both hit pairs and reconstructed tracks. For central pseudorapidities (abs(eta)<0.5), the charged-hadron multiplicity density is dN/d(eta)[charged,abs(eta) < 0.5] = 5.49 +/- 0.01 (stat) +/- 0.17 (sys), a value obtained by combining the two methods. The result is compared to predictions from Monte Carlo event generators and to similar measurements made at lower collision energies.

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CMS Collaboration. 2015-11-11. Pseudorapidity distribution of charged hadrons in proton-proton collisions at sqrt(s) = 13 TeV. https://doi.org/10.1016/j.physletb.2015.10.004

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