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arXiv · 1809.09325

Independently Parameterised Momenta Variables and Monte Carlo IR Subtraction

Peter Cox·Tom Melia
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Abstract

We introduce a system of parameters for the Monte Carlo generation of Lorentz invariant phase space that is particularly well-suited to the treatment of the infrared divergences that occur in the most singular, Born-like configurations of $1\to n$ QCD processes. A key feature is that particle momenta are generated independently of one another, leading to a simple parameterisation of all such IR limits. We exemplify the use of these variables in conjunction with the projection to Born subtraction technique at next-to-next-to-leading order. The geometric origins of this parameterisation lie in a coordinate chart on a Grassmannian manifold.

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Peter Cox, Tom Melia. 2018-09-25. Independently Parameterised Momenta Variables and Monte Carlo IR Subtraction. https://doi.org/10.1007/jhep12(2018)038

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