Unified Origin for Baryonic Visible Matter and Antibaryonic Dark Matter

We present a novel mechanism for generating both the baryon and dark matter densities of the Universe. A new Dirac fermion $X$ carrying a conserved baryon number charge couples to the standard model quarks as well as a GeV-scale hidden sector. $CP$-violating decays of $X$, produced nonthermally in low-temperature reheating, sequester antibaryon number in the hidden sector, thereby leaving a baryon excess in the visible sector. The antibaryonic hidden states are stable dark matter. A spectacular signature of this mechanism is the baryon-destroying inelastic scattering of dark matter that can annihilate baryons at appreciable rates relevant for nucleon decay searches.

Figure 1

Tree-level and one-loop graphs for decay $X_1\to udd$.

Figure 2

Diagram for representative induced nucleon decay processes $pY\to K^{+}{\Phi }^{*}$ and $p\Phi \to K^{+}\overline{Y}$.