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arXiv · 1912.06271

Two-Loop QCD Helicity Amplitudes for Higgs Production Associated with a Vector Boson through Bottom Quark Annihilation

Taushif Ahmed·A. H. Ajjath·Long Chen·Prasanna K. Dhani·Pooja Mukherjee·V. Ravindran
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Abstract

We present the two-loop QCD corrections to the amplitude of the Higgs production associated with a $Z$ boson via the bottom quark-antiquark annihilation channel with a non-vanishing bottom-quark Yukawa coupling. The computation is performed by projecting the D-dimensional scattering amplitude directly onto a set of Lorentz structures related to the linear polarisation states of the $Z$ boson. We cross-check the finite remainders through a computation based on conventional form factor decomposition. We show that for physical observables, an ultimate D-dimensional form factor decomposition of amplitudes is not necessary which has a huge potential to simplify a multiloop computation. We compute numerically the resulting cross sections under the soft-virtual approximation to NNLO and find it three orders of magnitude smaller than that of the s-channel.

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Taushif Ahmed, A. H. Ajjath, Long Chen, Prasanna K. Dhani, Pooja Mukherjee, V. Ravindran. 2019-12-13. Two-Loop QCD Helicity Amplitudes for Higgs Production Associated with a Vector Boson through Bottom Quark Annihilation. https://arxiv.org/abs/1912.06271

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