Statistics of Primordial Density Perturbations from Discrete Seed Masses
Statistics of Primordial Density Perturbations from Discrete Seed Masses
复制标题
离散种子质量的原始密度扰动统计
DOI：
10.1086/170658
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
E. Bertschinger
中科院分区：
文献类型：
--
作者：
R. Scherrer;E. Bertschinger
考察了具有任意物质吸积的种子质量一般分布的密度扰动统计量。推导了功率谱、N点关联函数和密度分布函数的形式表达式。这些结果适用于种子质量不相关的情况，并导出了热暗物质和冷暗物质加重子吸积的功率谱。计算密度分布的约化矩(累积量)，并将其用于密度分布函数的级数展开。在种子质量分布为球形顶帽吸积的情况下，得到了密度分布函数的解析结果。更广泛地说，这种形式使得能够给出由离散的核的线性叠加产生的任何随机场的统计特性的完整表征。具体地说，该结果可以应用于通过用窗函数使离散的点集平滑而得到的密度场。
The statistics of density perturbations for general distributions of seed masses with arbitrary matter accretion is examined. Formal expressions for the power spectrum, the N-point correlation functions, and the density distribution function are derived. These results are applied to the case of uncorrelated seed masses, and power spectra are derived for accretion of both hot and cold dark matter plus baryons. The reduced moments (cumulants) of the density distribution are computed and used to obtain a series expansion for the density distribution function. Analytic results are obtained for the density distribution function in the case of a distribution of seed masses with a spherical top-hat accretion pattern. More generally, the formalism makes it possible to give a complete characterization of the statistical properties of any random field generated from a discrete linear superposition of kernels. In particular, the results can be applied to density fields derived by smoothing a discrete set of points with a window function.