论文标题
在具有巨大中微子的宇宙学中非线性功率谱的快速计算
Fast computation of non-linear power spectrum in cosmologies with massive neutrinos
论文作者
论文摘要
我们在宇宙学的红移空间星系功率谱上计算1循环校正,其中包含其他尺度,因此与Einstein-De保姆(EDS)不同的内核。具体而言,我们的方法是在存在大量中微子和一些修饰的重力模型的情况下针对宇宙学量身定制的。在本文中,我们专注于以前的情况。扰动核的贡献我们会注意到这些贡献是从对数增长因子$ f(k,t)$中出现的,该因子$ f(k,t)$,由于中微子自由流的速度,或者是从常用近似值$ f^2 =ω_m$的失败中出现的。后者的贡献使循环校正的计算非常缓慢,排除了参数估计的全形分析。但是,我们确定核的主要部分来自生长因子,使我们能够简化内核,但保留了中微子质量引入的特征自由流量表。此外,通过这种简化,可以利用FFTLOG方法来加快计算的速度。我们使用从Quijote模拟中提取的光环目录来验证我们的分析建模和数值方法,这与先验,已知的宇宙学参数良好一致。我们将我们的Python Code Folps $ν$公开,以计算一小部分的红移空间功率谱。可在https://github.com/henoriega/folps-nu上找到代码。
We compute 1-loop corrections to the redshift space galaxy power spectrum in cosmologies containing additional scales, and hence kernels different from Einstein-de Sitter (EdS). Specifically, our method is tailored for cosmologies in the presence of massive neutrinos and some modified gravity models; in this article we concentrate on the former case. The perturbative kernels have contributions that we notice appear either from the logarithmic growth factor $f(k,t)$, which is scale-dependent because of the neutrino free-streaming, or from the failure of the commonly used approximation $f^2=Ω_m$. The latter contributions make the computation of loop corrections quite slow, precluding full-shape analyses for parameter estimation. However, we identify that the dominant pieces of the kernels come from the growth factor, allowing us to simplify the kernels but retaining the characteristic free-streaming scale introduced by the neutrinos' mass. Moreover, with this simplification one can exploit FFTLog methods to speed up the computations even more. We validate our analytical modeling and numerical method with halo catalogs extracted from the Quijote simulations finding good agreement with the, a priori, known cosmological parameters. We make public our Python code FOLPS$ν$ to compute the redshift space power spectrum in a fraction of second. Code available at https://github.com/henoriega/FOLPS-nu.