Source of CP Violation for Baryon Asymmetry of the Universe

Abstract

The baryon asymmetry of the Universe requires CP violation, but the Standard Model falls short by a factor of $10^{-10}$ or more. Starting from a clue at the $B$ factories, we point out that the large Yukawa couplings of the sequential fourth generation $t^{\prime }$ and $b^{\prime }$ quarks can provide enhancement by a factor of over $10^{13}$, making the 2-3-4 generation quark sector a viable source of CP violation for the baryon asymmetry of the Universe. With recent hints of large $\sin 2{\Phi }_{B_s}$ in $B_s^0$-${\bar{B}}_s^0$ mixing from the Tevatron, the ultimate test would be to discover the $t^{\prime }$ and $b^{\prime }$ quarks at the Large Hadron Collider.

Comments: 4 pages, 2 figures, style change and other revisions; version rejected by PRL