Constraining the dark energy with galaxy cluster x-ray data
Constraining the dark energy with galaxy cluster x-ray data
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DOI：
10.1103/physrevd.68.023510
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发表时间：
2003-03
影响因子：
5
通讯作者：
J. Lima;J. V. Cunha;J. Alcaniz;J. Alcaniz
中科院分区：
文献类型：
--
作者：
J. Lima;J. V. Cunha;J. Alcaniz;J. Alcaniz
表征暗能量成分的状态方程受到钱德拉对星系团 X 射线光度的观测、重子物质密度的独立测量以及 HST 关键项目给出的哈勃参数的最新测量的约束。通过假设由具有状态方程 $p_x = \omega \rho_x$ 的“精髓”组件驱动的空间平坦场景，我们对宇宙学参数 $\omega$ 和 $\Omega_{\rm{m}}$ 施加以下限制： (i) $-1 \leq \omega \leq -0.55$ 和 $\Omega_{\rm m} = 0.32^{+0.027}_{-0.014}$ (1$\sigma$) 如果暗能量的状态方程限制在区间 $-1 \leq \omega < 0$ (\emph{usual} 精华) 且 (ii) $\omega = -1.29^{+0.686}_{-0.792}$ 和 $\Omega_{\rm{m}} = 0.31^{+0.037}_{-0.034}$ ($1\sigma$) 如果 $\omega$ 违反零能量条件并假设值 $< -1$ （\emph{扩展}精髓或“幻影”能量）。这些结果与基于超新星观测、大尺度结构和宇宙背景辐射的各向异性的独立研究非常一致。
The equation of state characterizing the dark energy component is constrained by combining Chandra observations of the X-ray luminosity of galaxy clusters with independent measurements of the baryonic matter density and the latest measurements of the Hubble parameter as given by the HST key project. By assuming a spatially flat scenario driven by a "quintessence" component with an equation of state $p_x = \omega \rho_x$ we place the following limits on the cosmological parameters $\omega$ and $\Omega_{\rm{m}}$: (i) $-1 \leq \omega \leq -0.55$ and $\Omega_{\rm m} = 0.32^{+0.027}_{-0.014}$ (1$\sigma$) if the equation of state of the dark energy is restricted to the interval $-1 \leq \omega < 0$ (\emph{usual} quintessence) and (ii) $\omega = -1.29^{+0.686}_{-0.792}$ and $\Omega_{\rm{m}} = 0.31^{+0.037}_{-0.034}$ ($1\sigma$) if $\omega$ violates the null energy condition and assume values $< -1$ (\emph{extended} quintessence or ``phantom'' energy). These results are in good agreement with independent studies based on supernovae observations, large-scale structure and the anisotropies of the cosmic background radiation.