Determination ofαs(Mτ2)from improved fixed order perturbation theory
نویسندگان
چکیده
منابع مشابه
αs and the τ hadronic width: fixed-order, contour- improved and higher-order perturbation theory
The determination of αs from hadronic τ decays is revisited, with a special emphasis on the question of higher-order perturbative corrections and different possibilities of resumming the perturbative series with the renormalisation group: fixed-order (FOPT) vs. contour-improved perturbation theory (CIPT). The difference between these approaches has evolved into a systematic effect that does not...
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One of the largest theoretical uncertainties assigned to the strong coupling constant αs as determined from hadronic tau decays stems from the differences in the results for Fixed Order Perturbation Theory (FOPT), Contour Improved Perturbation Theory (CIPT) and Renormalon Chain Perturbation Theory (RCPT). It is often argued that the three methods differ in the treatment of higher orders only an...
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The hadronic decay rate of the τ lepton serves as one of the most precise determinations of the QCD coupling αs. The dominant theoretical source of uncertainty at present resides in the seeming disparity of two approaches to improving the perturbative expansion with the help of the renormalisation group, namely fixed-order and contourimproved perturbation theory. In this work it is demonstrated...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2012
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.85.094018