Higgs-MediatedB0→μ+μ−in Minimal Supersymmetry
We demonstrate a new source for flavor-changing neutral currents within the minimal supersymmetric standard model. At moderate to large $\mathrm{tan}\ensuremath{\beta}$, it is no longer possible to diagonalize the masses of the quarks in the same basis as their Yukawa couplings. This generates flavor-violating couplings of the form ${\overline{b}}_{R}{d}_{L}\ensuremath{\varphi}$ and ${\overline{b}}_{R}{s}_{L}\ensuremath{\varphi}$ where $\ensuremath{\varphi}$ is any of the three neutral, physical Higgs bosons. These new couplings lead to rare processes in the $B$ system such as ${B}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ and ${B}^{0}\ensuremath{-}{\overline{B}}^{0}$ mixing. We show that the latter are anomalously suppressed, while the former is in the experimentally interesting range, with an observable signal possible at Run II of the Tevatron if ${m}_{A}\ensuremath{\lesssim}400--700\mathrm{GeV}$.