The Reach of Threshold-Corrected Dark QCD

Abstract

We consider a recently-proposed model which posits the existence of composite dark matter, wherein dark "quarks" transforming as fundamentals under an $SU(3)_d$ gauge group undergo a confining phase and form dark baryons. The model attempts to explain both the $\mathcal{O}(1)$ relic density ratio, $\Omega_{\mathrm{dark}}/\Omega_{\mathrm{baryon}}\sim 5.4$, as well as the asymmetric production of both dark and baryonic matter via leptogenesis. Though the solution of $\beta$ functions for $SU(3)_c$ and $SU(3)_d$ constitutes the main drive of the model, no threshold corrections were taken into account as the renormalization scale crosses the mass threshold of the heavy new fields in the model. We extend this work by explicitly calculating the threshold-corrected renormalization-group flow for the theory using an effective-field matching technique. We find that the theory has a much wider range of applicability than previously thought, and that a significant fraction of models (defined by the number of fields contained therein) is able to account for the observed relic density.