$\mathbb Z_2$-Stable Dark Matter via Broken $\text{SU}(5)$ Gauge Bosons

TL;DR

This paper proposes a dark matter model neutral under the Standard Model gauge group, stabilized by a $ ext{Z}_2$ symmetry, and interacts primarily through broken $ ext{SU}(5)$ gauge bosons, with implications for cosmological production.

Contribution

It introduces a novel dark matter sector coupled only to broken $ ext{SU}(5)$ gauge directions, providing a gauge-covariant framework and effective operators for interactions.

Findings

Dark matter is stabilized by an exact $ ext{Z}_2$ symmetry.

Derived effective operators and loop-induced couplings to gluons.

Consistent with cold dark matter phenomenology and cosmological production mechanisms.

Abstract

I construct and analyze a dark matter sector that is neutral under the unbroken Standard Model gauge group and couples only to the broken $\text{SU}(5)$ gauge directions, the leptoquark vectors $X,Y$. An exact $\mathbb Z_2$ renders the dark matter stable. I give a gauge-covariant definition of projectors onto the unbroken Standard Model and broken ($X,Y$) subspaces, demonstrate that the covariant derivative of dark matter selects only $X,Y$, and integrate out $X,Y$ at tree level to obtain the leading effective operators. I also derive the loop-induced $\chi^2\,G^a_{\mu\nu}G^{a\mu\nu}$ coupling to gluons, prove color neutrality, and show consistency with cold dark matter phenomenology. Cosmological production proceeds via UV freeze-in or even more suppressed channels in.