Constraints on the interacting dark energy with Hubble parameter data and other observational data

Abstract

We constrain an interacting dark energy model with the Hubble parameter data ( OHD ), as well as the cosmic microwave background ( CMB ) observations from the Planck first data release, the baryonic acoustic oscillation ( BAO ) observations and the type Ia supernovae ( SNe ) data. The model parameters are determined by applying the maximum likelihood method of X 2 fitting by using the Markov Chain Monte Carlo (MCMC) method. The best-fit values of the model parameters with OHD + SNe + CMB + BAO are and Ωm =0.2919-0.0075+0.0075(1σ)-0.0144+0.0151(2σ), wX =-1.0374-0.0452+0.0453(1σ)-0.0886+0.0898(2σ), ξ =3.0976-0.1609+0.1600(1σ)-0.3189+0.3153(2σ), and H0 =69.6479-0.8563+0.8580(1σ)-1.6768+1.6919(2σ). The energy is transferred from dark energy to dark matter. The coincidence problem is slightly alleviated in 1 s range. For comparison, we constrain this model with OHD+BAO+CMB and SNe+CMB + BAO . The results are as follows: (1) It is shown that the OHD can give more stringent constraints on the interacting dark energy model when combined with SNe , CMB and BAO observations, OHD has the potential to alleviate coincidence problem. (2) The special case ( ξ +3 wX , corresponding to the ΛCDM model with no interaction) is within 1 σ confidence level with the OHD + CMB + BAO , SNe + CMB + BAO , and OHD + SNe + CMB + BAO combinations.