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arXiv · hep-ph/9605341

Perturbative QCD approach and particle energy spectra

S. Lupia
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Abstract

The Modified Leading Log Approximation of QCD and the local parton hadron duality picture are shown to give a fully satisfactory description of data on charged particle energy spectra in $e^+e^-$ annihilation. The analysis of data in terms of moments points out the running of $α_s$ both at very low $cms$ energy (${\cal O}$(3 GeV)) and at very low particle energy (${\cal O}$(200-500 MeV)). The study of the universal soft limit of energy spectra at low particle energy is proposed as a test of QCD coherence. The extension of this approach at identified particles' spectra is discussed.

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S. Lupia. 1996-05-17. Perturbative QCD approach and particle energy spectra. https://arxiv.org/abs/hep-ph/9605341

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