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arXiv · hep-ph/9806244

Two-loop QCD corrections to top quark width

Andrzej Czarnecki·Kirill Melnikov
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Abstract

We present O(alpha_s^2) corrections to the decay t-->bW in the limit of a very large top quark mass, m_t >> m_W. We find that the O(alpha_s^2) effects decrease the top quark decay width Gamma_t by about 2%: Gamma_t = Gamma_0(1-0.8alpha_s(m_t)-1.7alpha_s^2). The complete corrections are smaller by about 24% than their estimate based on the BLM effects O(beta_0 alpha_s^2). We explain how to compute a new type of diagrams which contribute to Gamma(t --> bW) at the O(alpha_s^2) level.

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Andrzej Czarnecki, Kirill Melnikov. 1998-06-03. Two-loop QCD corrections to top quark width. https://doi.org/10.1016/s0550-3213(98)00844-x

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