Speaker
Description
We present the most recent $BABAR$ searches for reactions that could simultaneously explain the presence of dark matter and the matter-antimatter asymmetry in the universe. This scenario predicts $B$-meson decays into a ordinary-matter baryon and a dark-sector anti-baryon $\psi_D$ with branching fractions accessible at the $B$ factories.
The results are based on the full data set of about 430 $\text{fb}^{-1}$ collected at the $\Upsilon(4S)$ resonance by the $BABAR$ detector at the PEP-II collider.
We search, in particular, for decays like $B^{0}\to\psi_{D} {\cal B}$ where $\cal{B}$ is a baryon (proton, $\Lambda$, or $\Lambda_c$). The hadronic recoil method has been applied with one of the $B$ mesons from $\Upsilon(4S)$ decay fully reconstructed, while only one baryon is present in the signal $B$-meson side. The missing mass of signal $B$ meson is considered as the mass of the dark particle $\psi_{D}$. Stringent upper limits on the decay branching fraction are derived for $\psi_D$ masses between 1.0 and 4.2 GeV/c$^2$.
