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Indexed by:期刊论文

Date of Publication:2008-08-20

Journal:MODERN PHYSICS LETTERS A

Included Journals:SCIE、Scopus

Volume:23

Issue:25

Page Number:2067-2076

ISSN No.:0217-7323

Key Words:modified Chaplygin gas (MCG); dark energy; transition redshift; deceleration parameter

Abstract:In this paper, the 1 sigma confidence level of transition redshift and present deceleration parameter are studied using modified Chaplygin gas (MCG) model from recent observations: the 182 Gold SNe Ia, three-year WMAP, SDSS baryon acoustic peak and X-ray gas mass fraction in clusters. Concretely, the best fit values of the transition redshift and present deceleration parameter with the 1 sigma confidence level are z(T) = 0.45(-0.09)(+0.19) and q(0) = -0.64(-0.15)(+0.15), which indicate the best fit values of z(T) and q(0) for MCG case are surprisingly close to the central values given by Refs. 20 and 21. Furthermore, we plot the evolution of cosmological quantities from MCG model by using the best-fit parameters given by combining constraint, and compare them with Lambda CDM model.