State-of-the-Art Predictions for C-parameter and a Determination of α[subscript s]
Name
Stewart_State-of-the-Art Predictions.pdf
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Author(s)
Hoang, André H.
Kolodrubetz, Daniel W.
Mateu, Vicent
Stewart, Iain W
Alternative Title
State-of-the-Art Predictions for C-parameter and a Determination of αs
Date Issued
May 2016
Journal
Nuclear and Particle Physics Proceedings
Publisher
Elsevier
Citation
Hoang, André H. et al. “State-of-the-Art Predictions for C-Parameter and a Determination of Α[subscript s].” Nuclear and Particle Physics Proceedings 273–275 (2016): 2015–2021. © 2015 Elsevier
Version
Final published version
Abstract
The C-parameter event-shape distribution for e[superscript +]e[superscript −] annihilation into hadrons is computed in the framework of SCET including input from fixed-order perturbation theory. We calculate all missing ingredients for achieving N[superscript 3]LL resummation accuracy in the cross section, which is then matched onto O(α[superscript 3][subscript s]) fixed-order results. Hadronization power corrections are incorporated as a convolution with a nonperturbative shape function. Wide-angle soft radiation effects introduce an O(Λ[subscript QCD]) renormalon ambiguity in the cross section, which we cure by switching to the Rgap short-distance scheme. We also include hadron mass effects, but find their effect is rather small. Performing fits to the tail of the C-parameter distribution for many center of mass energies we find that the strong coupling constant is α[subscript s](m[subscript Z]) = 0.1121 ± 0.0015, with χ[superscript 2]/dof = 0.99.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution 4.0 International License
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DOI of Published Version
https://doi.org/10.1016/j.nuclphysbps.2015.09.326
