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arXiv · 2505.00652

Hadron multiplicity fluctuations in perturbative QCD

Yu. L. Dokshitzer·B. R. Webber
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Abstract

We examine hadron multiplicity fluctuations in hard processes and confront analytic QCD predictions with the pattern of multiplicity fluctuations observed in $e^+e^-$ annihilation and high-$p_t$ jets produced in $pp$ collisions at the LHC. Special emphasis is placed on high-multiplicity fluctuations in jets. Selecting events with hadronic multiplicity exceeding the average value by a factor of 3 or more in various processes has been a source of conundrums for many years. We discuss two recent high-multiplicity puzzles and attempt to reveal their common origin.

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Yu. L. Dokshitzer, B. R. Webber. 2025-05-01. Hadron multiplicity fluctuations in perturbative QCD. https://arxiv.org/abs/2505.00652

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