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
exotic $B$-meson decays of the kind $B\to\psi_{D} {\cal B}$, where
$\cal{B}$ is an ordinary matter baryon (proton, $\Lambda$, or
$\Lambda_c$) and $\psi_D$ is a dark-sector anti-baryon, with
branching fractions accessible at the $B$ factories. 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 0.5 and 4.3 GeV/c$^2$. The results are
based on the full data set of about 430 fb$^{-1}$ collected at the
$\Upsilon(4S)$ resonance by the $BABAR$ detector at the PEP-II
collider.