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

An investigation of the polar angle distribution of charged hadrons is pres ented 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 d istribution the longitudinal, sigma (L), and transverse, sigma (T), cross-s ection relative to the total hadronic are determined at an average energy s cale 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 t he 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 agreemen t with the world average value of alpha (S) evolved to an energy scale of 3 6.6 GeV. (C) 2001 Elsevier Science B.V. All rights reserved.