摘要
We propose a new type of dark energy (DE) model, in which the equation of state of DE ω de is a simple function of the fractional energy density de instead of the redshift z. We assume three DE models of this type, and fit them with present observations to get constraints of DE, which are also compared with the CPL model. It is shown that a suitable ω de (Ωde ) model can give smaller χ2 or smaller errors of ω de than that of the CPL model. This new type of DE model can help to study the essential properties and nature of DE.
We propose a new type of dark energy （DE） model, in which the equation of state of DE wae is a simple function of the fractional energy density Ωde instead of the redshift z. We assume three DE models of this type, and fit them with present observations to get constraints of DE, which are also compared with the CPL model. It is shown that a suitable wda,（Ωde） model can give smaller X2 or smaller errors of wde than that of the CPL model. This new type of DE model can help to study the essential properties and nature of DE.
基金
Supported in part by the National Natural Science Foundation of China under Grant No. 11147186
Zhejiang Provincial Natural Science Foundation of China under Grant No. LQ12A05004 and Grant from Hangzhou Normal University
