Measurement of the longitudinal and transverse cross-section in e(+)e(-) annihilation at root s=35-44 GeV

摘要

An investigation of the polar angle distribution of charged hadrons is presented using data taken by the JADE experiment at the PETRA e+e(-) collider at centre-of-mass energies of 35 and 44 GeV. From fits to the polar angle distribution the longitudinal, sigma (L), and transverse, sigma (T), cross-section relative to the total hadronic are determined at an average energy scale of 36.6 GeV. The results are sigma (L)/sigma (tot) = 0.067 +/- 0.013, sigma (T)/sigma (tot) = 0.933 -/+ 0.013, where total errors are given and the results are exactly anticorrelated. Using the next-to-leading order QCD prediction for the longitudinal cross-section, the value alpha (S)(36.6 GeV) = 0.150 +/- 0.025 of the strong coupling constant is obtained in agreement with the world average value of alpha (S) evolved to an energy scale of 36.6 GeV. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 25]