In order to test the possible interaction between dark energy and dark matter , we investigate observational constraints on a phenomenological scenario , in which the ratio between the dark energy and matter densities is proportional to the power law case of the scale factor , r \equiv ( \rho _ { X } / \rho _ { m } ) \propto a ^ { \xi } .
By using the Markov chain Monte Carlo method , we constrain the phenomenological interacting dark energy model with the newly revised H ( z ) data , as well as the cosmic microwave background ( CMB ) observation from the 7-year Wilkinson Microwave Anisotropy Probe ( WMAP7 ) results , the baryonic acoustic oscillation ( BAO ) observation from the spectroscopic Sloan Digital Sky Survey ( SDSS ) data release 7 ( DR7 ) galaxy sample and the type Ia supernovae ( SNe Ia ) from Union2 set .
The best-fit values of the model parameters are \Omega _ { m 0 } = 0.27 _ { -0.02 } ^ { +0.02 } ( 1 \sigma ) _ { -0.03 } ^ { +0.04 } ( 2 \sigma ) , \xi = 3.15 _ { -0.50 } ^ { +0.48 } ( 1 \sigma ) _ { -0.71 } ^ { +0.72 } ( 2 \sigma ) , and w _ { X } = -1.05 _ { -0.14 } ^ { +0.15 } ( 1 \sigma ) _ { -0.21 } ^ { +0.21 } ( 2 \sigma ) , which are more stringent than previous results .
These results show that the standard \Lambda CDM model without any interaction remains a good fit to the recent observational data ; however , the interaction that the energy transferring from dark matter to dark energy is slightly favored over the interaction from dark energy to dark matter .
It is also shown that the H ( z ) data can give more stringent constraints on the phenomenological interacting scenario when combined to CMB and BAO observations , and the confidence regions of H ( z ) +BAO+CMB , SNe+BAO+CMB , and H ( z ) +SNe+BAO+CMB combinations are consistent with each other .