Higgs boson decays into a pair of heavy vector quarkonia

TL;DR

This paper investigates rare Higgs decays into heavy vector quarkonia, revealing significant contributions from transverse polarization channels and predicting very low branching ratios, which could be tested in future experiments.

Contribution

It introduces a comprehensive analysis including transverse polarization contributions in Higgs decays to heavy quarkonia, expanding beyond previous longitudinal-only considerations.

Findings

Branching ratios around 10^{-10} predicted.

Transverse polarization channels significantly contribute.

Decays are below current experimental bounds.

Abstract

Rare Higgs decays into a pair of heavy vector quarkonia, $h\to VV$ ($V=J/\Psi$, $\Upsilon$ etc.), have been investigated in the standard model. Different from the past literature in which these decays are thought to be only dominated by the longitudinally polarized final states, we also include the transitions, which proceed through $h\to \gamma^*\gamma^*$/$h\to V\gamma^*$, followed by $\gamma^*\to V$. The final vector quarkonia via these ways are dominantly transversely polarized. Our calculation however shows that these transitions could lead to significant contributions to the decay rate, especially for the charmonium final states. The total branching ratios of these processes are predicted to be around $10^{-10}$, far below the current experimental upper bounds. Hopefully, experimental studies of these very rare decays in future high-precision experimental facilities might be interesting both to test the standard model and to look for new physics scenarios.