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arXiv · hep-ph/9509249

Testing the running of the QCD coupling in particle energy spectra

Sergio Lupia·Wolfgang Ochs
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Abstract

The spectra of charged particles in the energy variable $ξ= \log 1/x$ (``the hump backed plateau'') are analyzed in terms of moments in order to investigate the sensitivity to the running of $α_s$ in particular towards small scales, and to further test thereby the local parton hadron duality picture. The modified leading log approximation (MLLA) of QCD provides a very satisfying description of the $e^+e^-$ data in the full range of c.m. energies from about 1 up to 91 GeV. The same calculation but with fixed coupling $α_s$ yields moments which are inconsistent with the data already close to threshold. In particular the soft particles ($E\le 1$~GeV) reflect directly the running of $α_s$.

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Sergio Lupia, Wolfgang Ochs. 1995-09-07. Testing the running of the QCD coupling in particle energy spectra. https://doi.org/10.1016/0370-2693(95)01270-2

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