alpha_s from tau decays: Contour-improved versus fixed-order summation in a new QCD perturbation expansion

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F09%3A00345228" target="_blank" >RIV/68378271:_____/09:00345228 - isvavai.cz</a>

Result on the web

—

DOI - Digital Object Identifier

—

Result language

angličtina

Original language name

alpha_s from tau decays: Contour-improved versus fixed-order summation in a new QCD perturbation expansion

Original language description

We consider the determination of $/alpha_s$ from ? hadronic decays, by investigating the CIPT and the FOPT renormalization group summations in the frame of a new perturbation expansion of QCD, which incorporates in a systematic way the available information about the divergent character of the series. The new expansion functions are defined by the analytic continuation in the Borel complex plane, achieved through an optimal conformal mapping. Using a model discussed by Beneke and Jamin, we show that thenew CIPT approaches the true results with great precision when the perturbative order is increased, while the new FOPT gives a less accurate description in the regions where the imaginary logarithms present in the expansion of the running coupling are large. From the new CIPT we predict $/alpha_s(m_/tau^2)= 0.320 ^{+0.011}_{-0.009}$.

Czech name

—

Czech description

—

Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BF - Elementary particle theory and high energy physics

OECD FORD branch

—

Project

<a href="/en/project/LA08015" target="_blank" >LA08015: Collaboration of the Czech Republic with CERN</a><br>

Continuities

Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2009

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

European Physical Journal C

ISSN

1434-6044

e-ISSN

—

Volume of the periodical

64

Issue of the periodical within the volume

1

Country of publishing house

DE - GERMANY

Number of pages

11

Pages from-to

—

UT code for WoS article

000271119700004

EID of the result in the Scopus database

—