Nonbaryonic dark matter and scalar field coupled with a transversal
  interaction plus decoupled radiation
  We analyze a universe filled with interacting dark matter, a scalar field
accommodated as dark radiation along with dark energy plus a decoupled
radiation term within the framework of spatially flat
Friedmann-Robertson-Walker (FRW) spacetime. We work in a three-dimensional
internal space spanned by the interaction vector and use a transversal
interaction $\mathbf{Q_t}$ for solving the source equation in order to find all
the interacting component energy densities. We asymptotically reconstruct the
scalar field and potential from an early radiation era to the late dominate
dark energy one, passing through an intermediate epoch dominated by dark
matter. We apply the $\chi^{2}$ method to the updated observational Hubble data
for constraining the cosmic parameters, contrast with the Union 2 sample of
supernovae, and analyze the amount of dark energy in the radiation era. It
turns out that our model fulfills the severe bound of $\Omega_{\rm
\phi}(z\simeq 1100)<0.018$ at $2\sigma$ level, is consistent with the recent
analysis that includes cosmic microwave background anisotropy measurements from
the Atacama Cosmology Telescope and the South Pole Telescope along with the
future constraints achievable by Planck and CMBPol experiments, and satisfies
the stringent bound $\Omega_{\rm \phi}(z\simeq 10^{10})<0.04$ at $2\sigma$
level in the big-bang nucleosynthesis epoch.
