The hadronic fragmentation functions of the various quark flavours and of gluons are measured in a study of the inclusive hadron production from Z(0) decays with the DELPHI detector and are compared with the fragmentation functions measured elsewhere at energies between 14 GeV and 91 GeV. A large scaling violation is observed, which is used to extract the strong coupling constant from a fit using a numerical integration of the second order DGLAP evolution equations. The result is alpha(s)(M-Z) = 0.124(-0.007)(+0.006) (exp) +/- 0.009(theory) where the first error represents the experimental uncertainty and the second error is due to the factorization and renormalization scale dependence. (C) 1997 Elsevier Science B.V.
A measurement of alpha(s) from the scaling violation in e(+)e(-) annihilation
BIANCHI, Fabrizio;MIGLIORE, Ernesto;ROMERO, Alessandra;
1997-01-01
Abstract
The hadronic fragmentation functions of the various quark flavours and of gluons are measured in a study of the inclusive hadron production from Z(0) decays with the DELPHI detector and are compared with the fragmentation functions measured elsewhere at energies between 14 GeV and 91 GeV. A large scaling violation is observed, which is used to extract the strong coupling constant from a fit using a numerical integration of the second order DGLAP evolution equations. The result is alpha(s)(M-Z) = 0.124(-0.007)(+0.006) (exp) +/- 0.009(theory) where the first error represents the experimental uncertainty and the second error is due to the factorization and renormalization scale dependence. (C) 1997 Elsevier Science B.V.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.