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论文类型：期刊论文

发表时间：2013-06-01

发表刊物：EUROPEAN PHYSICAL JOURNAL C

收录刊物：SCIE、Scopus

卷号：73

期号：6

页面范围：1-7

ISSN号：1434-6044

摘要：In this paper, we revisit viscous generalized Chaplygin gas (VGCG) as a unified dark fluid, which modifies the pressure only by redefining the effective pressure p(eff), according to p(eff) = p - root 3 zeta(0)rho, where zeta(0) is the newly added model parameter which characterizes the viscous property and can be determined by the cosmic observations. By using the currently available cosmic observational data from WMAP, BAO, and SN Ia, the model parameter space is obtained via a Markov Chain Monte Carlo method: zeta(0) = 0.000708(-0.00155-0.00311-0.00503)(+0.00151+0.00275+0.00425) in 1, 2, 3 sigma regions. The results show that the viscous effect is very small due the value zeta(0) approximate to 0 and the VGCG model can match observational data points as well as Lambda CDM model.