Quick Search:

uzh logo
Browse by:
bullet
bullet
bullet
bullet

Zurich Open Repository and Archive 

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-30917

Dissertori, G; Gehrmann-De Ridder, A; Gehrmann, T; Glover, E; Heinrich, G; Luisoni, G; Stenzel, H (2009). Determination of the strong coupling constant using matched NNLO+NLLA predictions for hadronic event shapes in e+e− annihilations. Journal of High Energy Physics, (8):036.

[img] PDF (Verlags-PDF) - Registered users only
1MB
[img]
Preview
Accepted Version
PDF
1MB

Abstract

We present a determination of the strong coupling constant from a fit of QCD predictions for six event-shape variables, calculated at next-to-next-to-leading order (NNLO) and matched to resummation in the next-to-leading-logarithmic approximation (NLLA). These event shapes have been measured in e+e− annihilations at LEP, where the data we use have been collected by the ALEPH detector at centre-of-mass energies between 91 and 206 GeV. Compared to purely fixed order NNLO fits, we observe that the central fit values are hardly affected, but the systematic uncertainty is larger because the NLLA part re-introduces relatively large uncertainties from scale variations. By combining the results for six event-shape variables and eight centre-of-mass energies, we find αs(MZ) = 0.1224 ± 0.0009 (stat) ± 0.0009 (exp) ± 0.0012 (had) ± 0.0035 (theo), which improves previously published measurements at NLO+NLLA. We also carry out a detailed investigation of hadronisation corrections, using a large set of Monte Carlo generator predictions.

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Physics Institute
DDC:530 Physics
Uncontrolled Keywords:Jets; LEP HERA and SLC Physics; NLO Computations; QCD
Language:English
Date:2009
Deposited On:22 Feb 2010 11:48
Last Modified:05 Jun 2014 09:21
Publisher:Institute of Physics Publishing
ISSN:1029-8479
Publisher DOI:10.1088/1126-6708/2009/08/036
Related URLs:http://arxiv.org/abs/0906.3436
Citations:Web of Science®. Times Cited: 22
Google Scholar™
Scopus®. Citation Count: 20

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page