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arXiv · 1210.2808

Top-Quark Decay at Next-to-Next-to-Leading Order in QCD

Jun Gao·Chong Sheng Li·Hua Xing Zhu
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Abstract

We present the complete calculation of the top-quark decay width at next-to-next-to-leading order in QCD, including next-to-leading electroweak corrections as well as finite bottom quark mass and $W$ boson width effects. In particular, we also show the first results of the fully differential decay rates for top-quark semileptonic decay $t\to W^+(l^+\nu)b$ at next-to-next-to-leading order in QCD. Our method is based on the understanding of the invariant mass distribution of the final-state jet in the singular limit from effective field theory. Our result can be used to study arbitrary infrared-safe observables of top-quark decay with the highest perturbative accuracy.

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Jun Gao, Chong Sheng Li, Hua Xing Zhu. 2012-10-10. Top-Quark Decay at Next-to-Next-to-Leading Order in QCD. https://doi.org/10.1103/physrevlett.110.042001

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