Change search
ReferencesLink to record
Permanent link

Direct link
Degeneracy relations in QCD and the equivalence of two systematic all-orders methods for setting the renormalization scale
Show others and affiliations
2015 (English)In: Physics Letters B, ISSN 0370-2693, Vol. 748, 13-18 p.Article in journal (Refereed) Published
Abstract [en]

The Principle of Maximum Conformality (PMC) eliminates QCD renormalization scale-setting uncertainties using fundamental renormalization group methods. The resulting scale-fixed pQCD predictions are independent of the choice of renormalization scheme and show rapid convergence. The coefficients of the scale-fixed couplings are identical to the corresponding conformal series with zero beta-function. Two all-orders methods for systematically implementing the PMC-scale setting procedure for existing high order calculations are discussed in this article. One implementation is based on the PMC-BLM correspondence (PMC-I); the other, more recent, method (PMC-II) uses the R-delta-scheme, a systematic generalization of the minimal subtraction renormalization scheme. Both approaches satisfy all of the principles of the renormalization group and lead to scale-fixed and scheme-independent predictions at each finite order. In this work, we show that PMC-I and PMC-II scale-setting methods are in practice equivalent to each other. We illustrate this equivalence for the four-loop calculations of the annihilation ratio Re+e- and the Higgs partial width Gamma(H -> b (b) over bar). Both methods lead to the same resummed ('conformal') series up to all orders. The small scale differences between the two approaches are reduced as additional renormalization group {beta(i)}-terms in the pQCD expansion are taken into account. We also show that special degeneracy relations, which underly the equivalence of the two PMC approaches and the resulting conformal features of the pQCD series, are in fact general properties of non-Abelian gauge theory. (C) 2015 The Authors. Published by Elsevier B.V.

Place, publisher, year, edition, pages
2015. Vol. 748, 13-18 p.
Keyword [en]
National Category
Astronomy, Astrophysics and Cosmology
URN: urn:nbn:se:kth:diva-173418DOI: 10.1016/j.physletb.2015.06.056ISI: 000359146200004ScopusID: 2-s2.0-84934325164OAI: diva2:853698

QC 20150914

Available from: 2015-09-14 Created: 2015-09-11 Last updated: 2015-09-14Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus
In the same journal
Physics Letters B
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 25 hits
ReferencesLink to record
Permanent link

Direct link