Measurement of Normalised Multi-jet Cross Sections using Regularised Unfolding and Extraction of alpha_s(MZ) in DIS at High Q2

Abstract

New results on normalised inclusive jet, dijet and trijet differential cross sections in neutral current DIS based on a regularised unfolding procedure are presented. Compared to a previously published result on normalised multi-jet cross sections, the new features are an extended range in jet pseudorapidity, an improved hadronic energy scale uncertainty of 1% and the application of an unfolding procedure. The normalised jet cross sections are compared to QCD calculations at NLO. The value of the strong coupling determined from the normalised inclusive jet, dijet and trijet measurements simultaneously is alpha_s(MZ) = 0.1163 +/- 0.0008 (exp.) +/- 0.0011 (sys.) +0.0044 / -0.0035 (theo.) +/- 0.0014 (PDF).

On behalf of the H1 Collaboration, 4 pages, 1 figures, to be published in the Proceedings of the XX International Workshop on Deep Inelastic Scattering, University of Bonn, 26-30th March 2012