Response approach to the integrated shear 3-point correlation function: the impact of baryonic effects on small scales
Response approach to the integrated shear 3-point correlation function: the impact of baryonic effects on small scales
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积分剪切三点相关函数的响应方法：重子效应对小尺度的影响
DOI：
10.1093/mnras/stac2046
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发表时间：
2022
影响因子：
4.8
通讯作者：
A. Barreira
中科院分区：
文献类型：
--
作者：
A. Halder;A. Barreira
积分剪切 3 点相关函数 ζ± 是宇宙剪切场的高阶统计量，描述了场中长波长特征对 2 点相关函数 ψ± 的调制。在这里，我们引入了一种新的理论模型来计算 z±，该模型在小角度尺度上是准确的，并且允许考虑重子反馈效应。我们的模型建立在这样的认识之上：小尺度 z± 由压缩极限下的非线性物质双谱主导，可以使用非线性物质功率谱及其对密度和潮汐场扰动的一阶响应函数来准确评估。我们通过证明我们的模型再现了模拟宇宙剪切图中测量的小尺度 z± 来证明模型的准确性。重子反馈的影响只有通过对非线性物质功率谱的相应影响才能有效地进入，从而允许解释这些对 ze± 的天体物理影响，类似于它们目前对 ze± 的解释方式。使用简单的理想化 Fisher 矩阵预测进行类似 DES 的调查，我们发现，与 xi± 相比，组合的 $\xi _{\pm }\ \&\ \zeta _{\pm }$ 分析可以导致对宇宙学参数（例如 σ8 或状态参数 w0 的暗能量方程）的约束提高 20-40\%$ 量级。我们发现重子反馈参数的约束有类似水平的改进，这增强了宇宙剪切数据不仅对宇宙学而且对天体物理反馈模型获得严格约束的前景。这些令人鼓舞的结果激发了未来对集成剪切 3 点相关函数的研究，以应用于实际调查数据。
The integrated shear 3-point correlation function ζ± is a higher-order statistic of the cosmic shear field that describes the modulation of the 2-point correlation function ξ± by long-wavelength features in the field. Here, we introduce a new theoretical model to calculate ζ± that is accurate on small angular scales, and that allows to take baryonic feedback effects into account. Our model builds on the realization that the small-scale ζ± is dominated by the nonlinear matter bispectrum in the squeezed limit, which can be evaluated accurately using the nonlinear matter power spectrum and its first-order response functions to density and tidal field perturbations. We demonstrate the accuracy of our model by showing that it reproduces the small-scale ζ± measured in simulated cosmic shear maps. The impact of baryonic feedback enters effectively only through the corresponding impact on the nonlinear matter power spectrum, thereby permitting to account for these astrophysical effects on ζ± similarly to how they are currently accounted for on ξ±. Using a simple idealized Fisher matrix forecast for a DES-like survey we find that, compared to ξ±, a combined $\xi _{\pm }\ \&\ \zeta _{\pm }$ analysis can lead to improvements of order $20-40\%$ on the constraints of cosmological parameters such as σ8 or the dark energy equation of state parameter w0. We find similar levels of improvement on the constraints of the baryonic feedback parameters, which strengthens the prospects for cosmic shear data to obtain tight constraints not only on cosmology but also on astrophysical feedback models. These encouraging results motivate future works on the integrated shear 3-point correlation function towards applications to real survey data.
通用滤波器修正的密度分裂统计模型
影响因子：
6.5
作者：
Burger P
通讯作者：
Burger P