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تسجيل مستخدم جديدEvolution of Massive Haloes in non-Gaussian Scenarios
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We have performed high-resolution cosmological N-body simulations of a concordance LCDM model to study the evolution of virialized, dark matter haloes in the presence of primordial non-Gaussianity. Following a standard procedure, departures from Gaussianity are modeled through a quadratic Gaussian term in the primordial gravitational potential, characterized by a dimensionless non-linearity strength parameter f_NL. We find that the halo mass function and its redshift evolution closely follow the analytic predictions of Matarrese et al.(2000). The existence of precise analytic predictions makes the observation of rare, massive objects at large redshift an even more attractive test to detect primordial non-Gaussian features in the large scale structure of the universe.
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