论文标题
与类星体的宇宙学：来自类星体哈勃图的Erosita的预测
Cosmology with quasars: predictions for eROSITA from a quasar Hubble diagram
论文作者
论文摘要
我们的小组开发了一种技术，该技术利用了观测到的类星体中观察到的非线性关系，以提供对其距离的独立测量，从而将类星体变成可标准化的蜡烛。目前，该技术主要基于X射线和光学/紫外线中公共目录的数据的类星体样本，并将超新星的哈勃图扩展到仍然很探索的红移范围（Z> 2）。从X射线的角度来看，我们现在正处于重大变化的前夕，因为即将到来的Erosita将为我们提供整个天空中最多约300万个活跃的银河系核。在这里，我们提出预测，以限制宇宙学参数，例如暗物质（$ω_{\ rm m} $），暗能量（$Ω__λ$）以及通过4年Allosita All-Sky调查的Quasars图的暗能状态（$ W $）方程的演变（$ w $）。我们的仿真表明，通过红移和宽带的光度信息进行补充的Erosita类星体将提供Z <2时最大的类星体样品，但是在较高的红移中可用于宇宙学的对象很少，因为Erosita将为Malmquist偏见而生存，因为Erosita将品尝X射线亮度亮度亮度亮度的亮点。准精确宇宙学的类星体哈勃图的力量在于高红移方案，可以在其中观察到类星体，直到红移〜7.5，这对于区分不同模型外推的必不可少。因此，为了使宇宙学具有竞争力，必须在RedShift Z> 3上与已经可用的类星体样本和专用（深）大型程序相辅相成。
Our group has developed a technique that makes use of the observed non-linear relation between the ultraviolet and the X-ray luminosity in quasars to provide an independent measurement of their distances, thus turning quasars into standardizable candles. This technique, at present, it is mostly based upon quasar samples with data from public catalogues both in the X-rays and in the optical/ultraviolet and extends the Hubble diagram of supernovae to a redshift range still poorly explored (z>2). From the X-ray perspective, we are now on the eve of a major change, as the upcoming mission eROSITA is going to provide us with up to ~3 millions of active galactic nuclei across the entire sky. Here we present predictions for constraining cosmological parameters such as the amount of dark matter ($Ω_{\rm m}$), dark energy ($Ω_Λ$) and the evolution of the equation of state of dark energy ($w$) through the Hubble diagram of quasars, based on the 4-year eROSITA all-sky survey. Our simulations show that the eROSITA quasars, complemented by redshift and broad-band photometric information, will supply the largest quasar sample at z<2, but with very few objects available for cosmology at higher redshifts that survives the cut for the Malmquist bias, as eROSITA will sample the brighter end of the X-ray luminosity function. The power of the quasar Hubble diagram for precision cosmology lies in the high-redshift regime, where quasars can be observed up to redshift ~7.5, essential to discriminate amongst different model extrapolations. Therefore, to be competitive for cosmology, the eROSITA quasar Hubble diagram must be complemented with the already available quasar samples and dedicated (deep) large programmes at redshift z>3.
