Non-perturbative QCD effects in $\eta_c$ and $\eta_b$ decays into baryons and WIMP scattering off nuclei

TL;DR

This paper estimates non-perturbative QCD effects in $ta_c$ and $ta_b$ decays into baryons and explores how instanton effects could influence WIMP-nucleus scattering, suggesting potential experimental detection and implications for dark matter interactions.

Contribution

It provides the first estimates of instanton-induced decay rates for $ta_b$ into baryons and discusses their impact on WIMP scattering cross sections, highlighting possible experimental signatures.

Findings

$ta_b$ decay channels into baryons could be detectable at future colliders.

Instanton effects may enhance spin-dependent WIMP-nucleus scattering cross sections.

Large uncertainties remain in quantifying the instanton-induced effects on WIMP interactions.

Abstract

In this work we estimate the helicity suppressed decay rates of $\eta_b$ resonances into baryon pairs due to instanton-induced effects by rescaling the corresponding partial widths of the experimentally measured branching ratios for the $\eta_c(1S) \to p\bar{p}$ and $\eta_c(1S) \to \Lambda\bar(\Lambda)$ decay modes. Thus we point out that both $\eta_b(1S) \to p\bar{p}$ and $\eta_b(1S) \to \Lambda\bar(\Lambda)$ channels could be detected at a Super B factory and LHC experiments. Furthermore, we examine related instanton-induced effects on WIMP scattering off nuclei concluding, albeit with large uncertainties, that they might enhance the spin-dependent cross section for a light pseudoscalar Higgs boson mediator, thereby inducing a dependence on the momentum transfer to the recoling nucleus.