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arXiv · 2401.05035

Beyond the Narrow-Width Limit for Off-Shell and Boosted Differential Top Quark Decays

André H. Hoang·Simon Plätzer·Christoph Regner·Ines Ruffa
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Abstract

The standard approaches for describing top quark production and its decay dynamics are currently mostly either based on the narrow-width (NW) limit or on off-shell fixed-order calculations. In this article we present a factorised approach for boosted top quarks that combines the properties of the NW limit and off-shell computations accounting for the dominant off-shell effects in an expansion in $m_t/Q$ with the hard scattering scale $Q$. We discuss the key ideas of our approach and show some preliminary results at tree-level.

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André H. Hoang, Simon Plätzer, Christoph Regner, Ines Ruffa. 2024-01-10. Beyond the Narrow-Width Limit for Off-Shell and Boosted Differential Top Quark Decays. https://arxiv.org/abs/2401.05035

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