Four loop anomalous dimensions of gradient operators in ${\phi^4}$ theory
نویسندگان
چکیده
منابع مشابه
Four-Loop Anomalous Dimensions for Radiative Flavour-Changing Decays
We evaluate the complete four-loop anomalous dimension matrix that is necessary for determining the effective flavour-changing neutral current couplings q̄qγ and q̄qg at the nextto-next-to-leading order in QCD. The resulting O(α s(μb)) correction to the B̄ → Xsγ branching ratio amounts to around −2.9% for μb = 5GeV, and −4.4% for μb = 2.5GeV.
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 1998
ISSN: 1434-6044,1434-6052
DOI: 10.1007/s100529800706