State-of-the-Art Predictions for C-parameter and a Determination of α <sub>s</sub>

Author(s)
Andre H. Hoang, Daniel W. Kolodrubetz, Vicent Mateu Barreda, Iain W. Stewart
Abstract

The C-parameter event-shape distribution for e

+e

- 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

3LL resummation accuracy in the cross section, which is then matched onto O(α

s

3) 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

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

s(m

Z)=0.1121±0.0015, with χ

2/dof=0.99.

Organisation(s)
Particle Physics, Research Platform Erwin Schrödinger International Institute for Mathematics and Physics
External organisation(s)
Massachusetts Institute of Technology
Journal
Nuclear and Particle Physics Proceedings
Volume
273-275
Pages
2015-2021
No. of pages
7
ISSN
2405-6014
DOI
https://doi.org/10.1016/j.nuclphysbps.2015.09.326
Publication date
2016
Peer reviewed
Yes
Austrian Fields of Science 2012
103012 High energy physics
Keywords
ASJC Scopus subject areas
Nuclear and High Energy Physics
Portal url
https://ucrisportal.univie.ac.at/en/publications/stateoftheart-predictions-for-cparameter-and-a-determination-of--s(555d4cc1-0e5c-4376-98a2-b894435ee653).html