It is known that the large-scale structure (LSS) mapped by a galaxy redshift survey is subject to distortions by the galaxies peculiar velocities. Besides the signatures generated in common N-point statistics, such as the anisotropy in the galaxy 2-pt correlation function, the peculiar velocities also induce distinct features in LSSs morphological properties, which are fully described by four Minkowski functionals (MFs), i.e., the volume, surface area, mean curvature and Euler characteristic (or genus). In this work, by using large suite of N-body simulations, we present and analyze these important features in the MFs of LSS on both (quasi-)linear and non-linear scales. With a focus on non-linear scale, we identify the features uniquely induced by the fingers-of-God effect that show up only on non-linear scales, especially in the surface-area weighted mean curvature in high density threshold regions. We also find the MFs may give competitive constraints on cosmological parameters compared to the power spectrum. These results are important for cosmological applications of MFs of LSS, and probablly open up a new way to study the peculiar velocity field itself.
تحميل البحث