论文标题
红移空间中大规模结构的EFT可能性
The EFT Likelihood for Large-Scale Structure in Redshift Space
论文作者
论文摘要
我们研究了红移空间中有偏见的示踪剂的EFT可能性，为此，Galaxy速度场的偏差扩展$ \ MATHBF {V} _g $起着基本作用。等效原则禁止$ \ mathbf {v} _g $的随机贡献以小$ k $生存。因此，按照衍生品的领先顺序，可能性$ {\ cal p} [\tildeΔ_g|δ，\！\！\ mathbf {v}] $观察一个红移空间的deldsenty $ \tildeΔ_g（\tildeΔ_g） $δ（\ mathbf {x}）$，$ \ mathbf {v}（\ mathbf {x}）$由REST-FRAME NOISE固定。如果这种噪音是具有恒定功率频谱的高斯人，则$ {\ cal p} [\tildeΔ_g|δ，\！\！\ mathbf {v}] $在$ \tildeΔ_g（\tildeΔ_g（\ tilde {\ tilde {\ tilde {\ mathbf {x x}}} $ sepliandies of coviance of by ins bias intshime of sepace Ontrimane的差异中，$也是高斯。 $δ（\ Mathbf {X}）$和$ \ Mathbf {V}（\ Mathbf {X}）$。然后，我们展示了如何将此结果与扰动理论匹配，如果在扰动中以二阶停止偏置扩展，则可以始终如一地忽略磁场依赖性协方差。我们在定性上讨论这如何影响基于EFT的远期建模的数值实现，以及当考虑到调查窗口功能时图像如何变化。
We study the EFT likelihood for biased tracers in redshift space, for which the bias expansion of the galaxy velocity field $\mathbf{v}_g$ plays a fundamental role. The equivalence principle forbids stochastic contributions to $\mathbf{v}_g$ to survive at small $k$. Therefore, at leading order in derivatives the form of the likelihood ${\cal P}[\tildeδ_g|δ,\!\mathbf{v}]$ to observe a redshift-space galaxy overdensity $\tildeδ_g(\tilde{\mathbf{x}})$ given a rest-frame matter and velocity fields $δ(\mathbf{x})$, $\mathbf{v}(\mathbf{x})$ is fixed by the rest-frame noise. If this noise is Gaussian with constant power spectrum, ${\cal P}[\tildeδ_g|δ,\!\mathbf{v}]$ is also a Gaussian in the difference between $\tildeδ_g(\tilde{\mathbf{x}})$ and its bias expansion: redshift-space distortions only make the covariance depend on $δ(\mathbf{x})$ and $\mathbf{v}(\mathbf{x})$. We then show how to match this result to perturbation theory, and that one can consistently neglect the field-dependent covariance if the bias expansion is stopped at second order in perturbations. We discuss qualitatively how this affects numerical implementations of the EFT-based forward modeling, and how the picture changes when the survey window function is taken into account.
