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Exact O(g^2 alpha_s) top decay width from general massive two-loop integrals

Adrian Ghinculov·York-Peng Yao
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Abstract

We calculate the b-dependent self-energy of the top quark at O(g^2 α_s) by using a general massive two-loop algorithm proposed in a previous article. From this we derive by unitarity the O(α_s) radiative corrections to the decay width of the top quark, where all effects associated with the $b$ quark mass are included without resorting to a mass expansion. Our results agree with the analytical results available for the O(α_s) correction to the top quark width.

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Adrian Ghinculov, York-Peng Yao. 2000-02-19. Exact O(g^2 alpha_s) top decay width from general massive two-loop integrals. https://doi.org/10.1142/s021773230000092x

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