论文标题
宇宙学参数对非线性处方的敏感性来自星系聚类
Sensitivity of Cosmological Parameter Estimation to Nonlinear Prescription from Galaxy Clustering
论文作者
论文摘要
下一代大规模调查以高分辨率探测非线性制度。基于这些观察结果进行可行的宇宙学推断需要对轻度非线性制度进行准确的理论建模。在这项工作中，我们研究了宇宙学参数测量的灵敏度，从未来的星系聚类探针到选择非线性处方的选择，最高为$ k _ {\ rm max} = 0.3〜h〜 \ rm {mpc}^{ - 1} $。特别是，当通过halofit拟合方案对中等非线性状态进行建模时，我们计算诱导的参数偏差。我们发现一些参数有明显的（$ \sim5σ$）偏差，并通过未来的欧几里得般调查。我们还探讨了不同观测设置和宇宙学场景的不同量表对参数估计的贡献，这是Halofit和Eftoflss的两个非线性处方的贡献。我们在分析中包括非线性理论的自由参数和银河系偏置的盲参数化。我们发现这些滋扰参数的边缘化显着增加了标准宇宙学参数的误差。这使得在转移到参数空间时，各种非线性处方的预测的差异较低。因此，对这些滋扰参数的更准确的建模将大大增强轻度非线性制度的宇宙学增益。
Next generation large scale surveys probe the nonlinear regime with high resolution. Making viable cosmological inferences based on these observations requires accurate theoretical modeling of the mildly nonlinear regime. In this work we investigate the sensitivity of cosmological parameter measurements from future probes of galaxy clustering to the choice of nonlinear prescription up to $k_{\rm max}=0.3~h~\rm{Mpc}^{-1}$. In particular, we calculate the induced parameter bias when the mildly nonlinear regime is modeled by the Halofit fitting scheme. We find significant ($\sim5σ$) bias for some parameters with a future Euclid-like survey. We also explore the contribution of different scales to the parameter estimation for different observational setups and cosmological scenarios, compared for the two nonlinear prescriptions of Halofit and EFTofLSS. We include in the analysis the free parameters of the nonlinear theory and a blind parametrization for the galaxy bias. We find that marginalization over these nuisance parameters significantly boosts the errors of the standard cosmological parameters. This renders the differences in the predictions of the various nonlinear prescriptions less effective when transferred to the parameter space. More accurate modeling of these nuisance parameters would therefore greatly enhance the cosmological gain from the mildly nonlinear regime.
