Electroweak baryogenesis and dark matter from a singlet Higgs
  If the Higgs boson H couples to a singlet scalar S via lambda_m |H|^2 S^2, a
strong electroweak phase transition can be induced through a large potential
barrier that exists already at zero temperature. In this case properties of the
phase transition can be computed analytically. We show that electroweak
baryogenesis can be achieved using CP violation from a dimension-6 operator
that couples S to the top-quark mass, suppressed by a new physics scale that
can be well above 1 TeV. Moreover the singlet is a dark matter candidate whose
relic density is < 3% of the total dark matter density, but which nevertheless
interacts strongly enough with nuclei (through Higgs exchange) to be just below
the current XENON100 limits. The DM mass is predicted to be in the range 80-160
GeV.
