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arXiv · 1611.07352

Computation of NLO Processes Involving Heavy Quarks Using Loop-Tree Duality

Abstract

We present a new method to compute higher-order corrections to physical cross-sections, at Next-to-Leading Order and beyond. This method, based on the Loop Tree Duality, leads to locally integrable expressions in four dimensions. By introducing a physically motivated momentum mapping between the momenta involved in the real and the virtual contributions, infrared singularities naturally cancel at integrand level, without the need to introduce subtraction counter-terms. Ultraviolet singularities are dealt with by using dual representations of suitable counter-terms, with some subtleties regarding the self-energy contributions. As an example, we apply this method to compute the $1\to2$ decay rate in the context of a scalar toy model with massive particles.

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Felix Driencourt-Mangin. 2016-11-22. Computation of NLO Processes Involving Heavy Quarks Using Loop-Tree Duality. https://doi.org/10.1063/1.4977166

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