English

Two-loop $\mathcal{N}=2$ SQCD amplitudes with external matter from iterated cuts

High Energy Physics - Theory 2019-10-08 v2 High Energy Physics - Phenomenology

Abstract

We develop an iterative method for constructing four-dimensional generalized unitarity cuts in N=2\mathcal{N} = 2 supersymmetric Yang-Mills (SYM) theory coupled to fundamental matter hypermultiplets (N=2\mathcal{N} = 2 SQCD). For iterated two-particle cuts,specifically those involving only four-point amplitudes, this implies simple diagrammatic rules for assembling the cuts to any loop order, reminiscent of the rung rule in N=4\mathcal{N} = 4 SYM. By identifying physical poles, the construction simplifies the task of extracting complete integrands. In combination with the duality between color and kinematics we construct all four-point massless MHV-sector scattering amplitudes up to two loops in N=2\mathcal{N} = 2 SQCD, including those with matter on external legs. Our results reveal chiral infrared-finite integrands closely related to those found using loop-level BCFW recursion. The integrands are valid in D6D\leq 6 dimensions with external states in a four-dimensional subspace; the upper bound is dictated by our use of six-dimensional chiral N=(1,0)\mathcal{N} = (1,0) SYM as a means of dimensionally regulating loop integrals.

Keywords

Cite

@article{arxiv.1811.09604,
  title  = {Two-loop $\mathcal{N}=2$ SQCD amplitudes with external matter from iterated cuts},
  author = {Gregor Kälin and Gustav Mogull and Alexander Ochirov},
  journal= {arXiv preprint arXiv:1811.09604},
  year   = {2019}
}

Comments

35 pages + appendices + references; 4 figures, 2 tables; journal version

R2 v1 2026-06-23T05:25:50.498Z