Hadron Multiplicity as the Limit of Jet Multiplicity at High Resolution *
نویسنده
چکیده
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 eeannihilation. The solution suggests that a final state hadron can be represented by a jet in the limit of small (nonperturbative) k⊥ cut-off Q0. In this description using as adjustable parameters only the QCD scale Λ and the cut-off Q0, the coupling αs can be seen to rise towards large values above unity at low energies.
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