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Indexed by:期刊论文

Date of Publication:2010-04-15

Journal:PHYSICAL REVIEW D

Included Journals:SCIE

Volume:81

Issue:8

ISSN No.:2470-0010

Abstract: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) = 0.0230(-0.0010-0.0014)(+0.0008+0.0012), alpha = 0.9788(-0.0927-0.1249)(+0.1297+0.1354), beta = 0.4739(-0.0723-0.0984)(+0.0793+0.1055), Omega(de0) = 0.7869(-0.0304-0.0455)(+0.0291+0.0370), Omega(m0) = 0.2131(-0.0291-0.0370)(+0.0304+0.0455), H-0 = 70.46(-2.97-4.02)(+2.82+3.89). In the nonflat model, the constraint results are found 1 sigma, 2 sigma region; Omega(b)h(2) = 0.0229(-0.0010-0.0014)(+0.0010+0.0013), Omega(k) = 0.0014(-0.0597-0.0743)(+0.0604+0.0604), alpha = 0.9637(-0.2840-0.3333)(+0.2291+0.2894), beta = 0.4712(-0.0756-0.0961)(+01412+0.1703), Omega(de0) = 0.7829(-0.2130-0.2386)(+0.1588+0.1901), Omega(m0) = 0.2157(-0.1012-0.1241)(+0.1562+0.1800), H-0 = 70.64(-3.32-4.45)(+2.74+3.52). 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) = -0.9278 +/- 0.0626, q(0) = -0.5951 +/- 0.0586 (flat case) and w(de0) = -0.9501 +/- 0.1442, q(0) = -0.06164 +/- 0.0805 (flat case) and w(de0) = -0.9501 +/- 0.1442, q(0) = -0.6164 +/- 0.0805 (nonflat case). Compared to the Lambda CDM model, it is found the current combined data sets do not favor the holographic dark energy model over the Lambda CDM model.