三百项目：通过星系团的模拟X射线和毫米波分析验证$H_0$推断
The Three Hundred Project: Validating $H_0$ inference from mock X-ray and millimetre analyses of galaxy clusters
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中文总结 AI 辅助
研究通过三百流体动力学模拟样本，评估X射线和毫米波分析中ICM温度形态假设差异，利用其统计行为联合推断星系团温度剖面，从而约束宇宙学参数，对哈勃常数$H_0$进行无偏估计，凸显联合观测的潜力。
中文摘要 AI 辅助
星系团中热力学量的测量受X射线和毫米波波段径向平均可观测量简化模型的影响不同，包括宇宙学模型和星系团内介质形态的假设。在从三百流体动力学模拟中提取的大量星系团样本中，评估了从X射线光谱或联合X射线和毫米波成像推断的ICM温度之间形态假设的系统差异。发现这些差异呈现出明确的统计行为，与星系团动力学和形态指标相关。然后研究了基于这种统计行为先验的星系团温度剖面联合推断如何约束从表观星系团大小推断的宇宙学参数。假设平坦的$\Lambda$CDM模型以及$\Omega_m$和氦丰度的先验，该方法能对哈勃常数$H_0$进行无偏估计，对于100和1000个星系团样本，精度分别约为4%和1.5%，最终受约0.6 - 0.8 km s⁻¹ Mpc⁻¹的系统不确定性限制。这项工作突出了星系团样本的联合X射线和毫米波观测对$H_0$进行严格约束的潜力。
英文摘要
Measurements of thermodynamical quantities in galaxy clusters are differently affected by simplified modelling of radially averaged observables in the X-ray and millimetre bands. This includes assumptions about the cosmological model and the morphology of the cluster intracluster medium (ICM). Within a large sample of clusters extracted from The Three Hundred hydrodynamical simulations, we assess the systematic differences expected from the morphological assumptions between ICM temperatures as inferred from X-ray spectroscopy or joint X-ray and millimetre imaging. We find that these differences show a well-defined statistical behaviour that correlates with the cluster dynamical and morphological indicators. We then investigate how joint inferences of cluster temperature profiles, a priori informed by this statistical behaviour, allow us to constrain cosmological parameters inferred from the apparent cluster sizes. Assuming a flat $Λ$ cold dark matter ($Λ$CDM) cosmology and priors on $Ω_\mathrm{m}$ and the helium abundance, this method provides us with unbiased estimates of the Hubble constant, $H_0$, characterised with a precision of about $4\%$ and $1.5\%$ for samples of 100 and 1000 clusters, respectively, and ultimately limited by systematic uncertainties of about $0.6$--$0.8\, {\rm km\, s^{-1} Mpc^{-1}}$. This work highlights the potential of joint X-ray and millimetre observations of galaxy cluster samples to place tight constraints on $H_0$.
