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arXiv · hep-ph/9709246

Hadron multiplicity as the limit of jet multiplicity at high resolution

Sergio Lupia·Wolfgang Ochs
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Abstract

Recently exact numerical results from the evolution equation for parton multiplicities in QCD jets have been obtained. A comparison with various approximate results is presented. A good description is obtained not only of the jet multiplicities measured at LEP-1 but also of the hadron multiplicities for $cms$ energies above 1.6 GeV in \epem annihilation. The solution suggests that a final state hadron can be represented by a jet in the limit of small (nonperturbative) $k_\perp$ cut-off $Q_0$. In this description using as adjustable parameters only the QCD scale $Λ$ and the cut-off $Q_0$, the coupling $α_s$ can be seen to rise towards large values above unity at low energies.

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Sergio Lupia, Wolfgang Ochs. 1997-09-04. Hadron multiplicity as the limit of jet multiplicity at high resolution. https://doi.org/10.1016/s0920-5632(97)01039-6

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