Kurtosis as a NonGaussian Signature of the LargeScale Velocity Field
Abstract
We discuss the nonlinear growth of the kurtosis of the smoothed peculiar velocity field (along an arbitrary direction), in an Einsteinde Sitter universe, induced by Gaussian primordial density fluctuations. Applying the perturbative theory, we show that, for different cosmological models, a departure from the original Gaussian distribution is gravitationally induced only on scales smaller than 2030 Mpc. Models with scalefree power spectrum P(k) is proportional to k^n^, with  1 < n <= 1, are also considered. A new statistics, independent of the power spectrum normalization and of time, is introduced to measure the kurtosis of the velocity field.
 Publication:

The Astrophysical Journal
 Pub Date:
 November 1994
 DOI:
 10.1086/174875
 arXiv:
 arXiv:astroph/9403035
 Bibcode:
 1994ApJ...436....5C
 Keywords:

 Cosmology;
 Equations Of Motion;
 Galactic Clusters;
 Kurtosis;
 Mathematical Models;
 Monte Carlo Method;
 Red Shift;
 Velocity Distribution;
 Galaxies;
 Normal Density Functions;
 Astrophysics;
 COSMOLOGY: THEORY;
 GALAXIES: CLUSTERING;
 COSMOLOGY: LARGESCALE STRUCTURE OF UNIVERSE;
 Astrophysics
 EPrint:
 10 pages in Latex (plus 2 figures in a separate file), PDcosmo/9401