Precise determination of αs from the C-parameter distribution

Autor(en)

Andre H. Hoang, Daniel W. Kolodrubetz, Vicent Mateu, Iain W. Stewart

Abstrakt

We present a global fit for αs(mZ), analyzing the available C-parameter data measured at center-of-mass energies between Q=35 and 207 GeV. The experimental data is compared to a N3LL'+O(αs3)+Ω1 theoretical prediction (up to the missing four-loop cusp anomalous dimension), which includes power corrections coming from a field-theoretical nonperturbative soft function. The dominant hadronic parameter is its first moment Ω1, which is defined in a scheme which eliminates the O(ΛQCD) renormalon ambiguity. The resummation region plays a dominant role in the C-parameter spectrum, and in this region a fit for αs(mZ) and Ω1 is sufficient. We find αs(mZ)=0.1123±0.0015 and Ω1=0.421±0.063 GeV with χ2/d.o.f.=0.988 for 404 bins of data. These results agree with the prediction of universality for Ω1 between thrust and C-parameter within 1-σ.

Organisation(en)

Teilchenphysik

Externe Organisation(en)

Massachusetts Institute of Technology

Journal

Physical Review D

Band

91

Anzahl der Seiten

24

ISSN

1550-7998

Publikationsdatum

05-2015

Peer-reviewed

Ja

ÖFOS 2012

103034 Teilchenphysik

Schlagwörter

ASJC Scopus Sachgebiete

Nuclear and High Energy Physics, Physics and Astronomy (miscellaneous)

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/560acb2c-bf3a-4b6d-a46f-4cc5d6395a23