Understand
In this paper, the holographic dark energy model with new infrared (IR) cut-off for both the flat case and the non-flat case are confronted with the combined constraints of current cosmological observations: type Ia Supernovae, Baryon Acoustic Oscillations, current Cosmic Microwave Background, and the observational hubble data.
- By utilizing the Markov Chain Monte Carlo (MCMC) method, we obtain the best fit values of the parameters with $1\sigma, 2\sigma$ errors in the flat model: $\Omega_{b}h^2=0.0233^{+0.0009 +0.0013}_{-0.0009 -0.0014}$, $\alpha=0.8502^{+0.0984 +0.1299}_{-0.0875 -0.1064}$, $\beta=0.4817^{+0.0842 +0.1176}_{-0.0773 -0.0955}$, $\Omega_{de0}=0.7287^{+0.0296 +0.0432}_{-0.0294 -0.0429}$, $\Omega_{m0}=0.2713^{+0.0294 +0.0429}_{-0.0296 -0.0432}$, $H_0=66.35^{+2.38 +3.35}_{-2.14 -3.07}$.
- In the non-flat model, the constraint results are found in $1\sigma, 2\sigma$ regions: $\Omega_{b}h^2=0.0228^{+0.0010 +0.0014}_{-0.0010 -0.0014}$, $\Omega_k=0.0305^{+0.0092 +0.0140}_{-0.0134 -0.0176}$, $\alpha=0.8824^{+0.2180 +0.2213}_{-0.1163 -0.1378}$, $\beta=0.5016^{+0.0973 +0.1247}_{-0.0871 -0.1102}$, $\Omega_{de0}=0.6934^{+0.0364 +0.0495}_{-0.0304 -0.0413}$, $\Omega_{m0}=0.2762^{+0.0278 +0.0402}_{-0.0320 -0.0412}$, $H_0=70.20^{+3.03 +3.58}_{-3.17 -4.00}$.
- In the best fit holographic dark energy models, the equation of state of dark energy and the deceleration parameter at present are characterized by $w_{de0}=-1.1414\pm0.0608, q_0=-0.7476\pm0.0466$ (flat case) and $w_{de0}=-1.0653\pm0.0661, q_0=-0.6231\pm0.0569$ (non-flat case).