arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0903.0131astro-ph.CO
收藏

高z宇宙示踪剂与暗能量状态方程

Alternative High-z Cosmic Tracers and the Dark Energy Equation of State

M. Plionis, R. Terlevich, S. Basilakos, F. Bresolin, E. Terlevich, J. Melnick, I. Georgantopoulos

摘要:

我们建议用另一种宇宙示踪剂来测量宇宙的暗能量状态方程和物质含量[w(z)& Ω_m]。我们提出的方法包括两个部分:(a)跟踪哈勃关系使用HII类星暴星系,作为SNIa的替代品,它可以检测到非常大的红移,z~4,和(b)测量集群模式的X射线选择AGN的中值红移~1。该方法的每个组成部分本身都可以提供对宇宙学参数的有趣约束,特别是在我们预期我们将显著减少相应的随机误差和系统误差的情况下。然而,通过加入它们的似然函数,我们将能够施加严格的宇宙学约束,打破暗能量状态方程(无论是常数还是变量)与宇宙物质含量之间已知的简并性,并提供一个强大的替代方法来测量暗能量对全球动力学和状态方程的贡献。对X射线选定的活动星系核(基于小型XMM调查)和目前最大的SNIa样本(Kowalski et al 2008)的初步联合分析提供:Omega_m=0.28^{+0.02}_{-0.04}和w=-1.0 +-0.1。

英文摘要:

We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Ω_m]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII-like starburst galaxies, as an alternative to SNIa, which can be detected up to very large redshifts, z~4, and (b) measuring the clustering pattern of X-ray selected AGN at a median redshift of ~1. Each component of the method can in itself provide interesting constraints on the cosmological parameters, especially under our anticipation that we will reduce the corresponding random and systematic errors significantly. However, by joining their likelihood functions we will be able to put stringent cosmological constraints and break the known degeneracies between the dark energy equation of state (whether it is constant or variable) and the matter content of the universe and provide a powerful and alternative rute to measure the contribution to the global dynamics, and the equation of state, of dark energy. A preliminary joint analysis of X-ray selected AGN (based on a small XMM survey) and the currently largest SNIa sample (Kowalski et al 2008), provides: Omega_m=0.28^{+0.02}_{-0.04} and w=-1.0 +-0.1.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑