Determination of αs at NLO*+NNLL from a global fit of the low-z parton-tohadron fragmentation functions in e+e− and DIS collisions
1 Sorbonne Université, UPMC Univ Paris 06, UMR 7589, LPTHE, F-75005, Paris, France
2 CNRS, UMR 7589, LPTHE, UPMC Univ. Paris 06, BP 126, 4 place Jussieu, F-75252 Paris Cedex 05, France
3 Department of Physics, P.O. Box 35, FI-40014 University of Jyväskylä, Jyväskylä, Finland
4 CERN, PH Department, CH-1211 Geneva 23, Switzerland
Published online: 24 March 2015
The QCD coupling αs is determined from a combined analysis of experimental e+e− and e±p jet data confronted to theoretical predictions of the energy evolution of the parton-to-hadron fragmentation functions (FFs) moments –multiplicity, peak, width, skewness– at low fractional hadron momentum z. The impact of approximate next-to-leading order (NLO*) corrections plus next-to-next-to-leading log (NNLL) resummations, compared to previous LO+NLL calculations, is discussed. A global fit of the full set of existing data, amounting to 360 FF moments at collision energies √s ≈ 1–200 GeV, results in αs(mZ2) = 0.1189−0.0014+0.0025 at the Z mass.
© Owned by the authors, published by EDP Sciences, 2015
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