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arXiv · 1610.04453

Note on recursion relations for the $\mathcal{Q}$-cut representation

Bo Feng·Song He·Rijun Huang·Ming-xing Luo
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Abstract

In this note, we study the $\mathcal{Q}$-cut representation by combining it with BCFW deformation. As a consequence, the one-loop integrand is expressed in terms of a recursion relation, i.e., $n$-point one-loop integrand is constructed using tree-level amplitudes and $m$-point one-loop integrands with $m\leq n-1$. By giving explicit examples, we show that the integrand from the recursion relation is equivalent to that from Feynman diagrams or the original $\mathcal{Q}$-cut construction, up to scale free terms.

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Bo Feng, Song He, Rijun Huang, Ming-xing Luo. 2016-10-14. Note on recursion relations for the $\mathcal{Q}$-cut representation. https://doi.org/10.1007/jhep01(2017)008

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