Impact of a Light Strange-Beauty Squark on $B_s$ Mixing and Direct Search

If the flavor symmetry underlying quark masses and mixings is Abelian, $s_R$-$b_R$ mixing would be close to maximal. With supersymmetry, this can drive a "strange-beauty" squark, $\widetilde{sb}_{1}$, to become rather light without adversely affecting $b\to s\gamma$, while low energy constraints imply that other squarks, gluinos and charginos are all at TeV scale. However, a light neutralino, $\widetilde \chi_1^0$, can evade the $b\to s\gamma$ constraint. The $\widetilde{sb}_{1}$, light or heavy, can contribute to $B_s$-$\bar B_s$ mixing and generate a CP violating phase. Direct search is analogous to usual $\tilde b \to b\widetilde \chi_1^0$, but existing bounds are weakened by possibility of $\widetilde{sb}_{1} \to s\widetilde \chi_1^0$. All three effects could be uncovered soon at the Tevatron.