A generalized equation of state for dark energy
  A generalized parameterization $w_\beta(z)$ for the dark energy equation of
state (EoS) is proposed and some of its cosmological consequences are
investigated. We show that in the limit of the characteristic dimensionless
parameter $\beta \to +1, 0$ and -1 some well-known EoS parameterizations are
fully recovered whereas for other values of $\beta$ the proposed
parameterization admits a wider and new range of cosmological solutions. We
also discuss possible constraints on the $w_\beta(z)$ parameters from current
observational data.
