On the $ZH$ amplitudes at two loop in QCD

Abstract

Through this article, we show that the amplitudes for the $b\bar{b}\to ZH$ in the presence of bottom-Higgs Yukawa coupling can be constructed, up to a few anomalous diagrams, solely from a set of vector form factors of properly grouped classes of diagrams. Thereby, we can completely bypass the subtle issues involving the chiral quantity ${\gamma }_5$. In the second part, we demonstrate that while computing the $q\bar{q}\to ZH$ amplitudes in Higgs effective field theory employing a non-anticommuting ${\gamma }_5$ in dimensional regularization, we need to introduce a four-point effective composite operator to the renormalized Lagrangian in order to retain the physical properties of the amplitude.

arXiv commentProceedings for the European Physical Society Conference on High Energy Physics (EPS-HEP2021), 26-30 July 2021