Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-16507
Dissertori, G; Gehrmann-DeRidder, A; Gehrmann, T; Glover , E W N; Heinrich, G; Stenzel, H (2008). First determination of the strong coupling constant using NNLO predictions for hadronic event shapes in e+e− annihilations. Journal of High Energy Physics, (2):040.
PDF (Accepted manuscript, Version 1)
PDF (Accepted manuscript, Version 2)
We present the first determination of the strong coupling constant from a fit of next-to-next-to-leading order QCD predictions to event-shape variables, measured in e+e− annihilations at LEP. The data have been collected by the ALEPH detector at centre-of-mass energies between 91 and 206 GeV. Compared to results of next-to-leading order fits we observe that the central fit values are lower by about 10 %, with considerably reduced scatter among the results obtained with different event-shape variables. The dominant systematic uncertainty from renormalization scale variations is reduced by a factor of two. By combining the results for several event-shape variables and centre-of-mass energies, we find αs(M2Z) = 0.1240 ± 0.0008 (stat) ± 0.0010 (exp) ± 0.0011 (had) ± 0.0029 (theo).
|Item Type:||Journal Article, not refereed, original work|
|Communities & Collections:||07 Faculty of Science > Institute of Theoretical Physics|
|Deposited On:||10 Mar 2009 11:28|
|Last Modified:||23 Nov 2012 14:07|
|Publisher:||Institute of Physics Publishing|
Users (please log in): suggest update or correction for this item
Repository Staff Only: item control page