Ellipsoidal Collapse and Previrialization
نویسندگان
چکیده
منابع مشابه
Ellipsoidal collapse and previrialization
We study the non-linear evolution of a dust ellipsoid, embedded in a Friedmann flat background universe, in order to determine the evolution of the density of the ellipsoid as the perturbation to it related detaches from general expansion and begins to collapse. We show that while the growth rate of the density contrast of a mass element is enhanced by the shear in agreement with Hoffman (1986a...
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N-body simulations have demonstrated a correlation between the properties of haloes and their environment. In this paper, we assess whether the ellipsoidal collapse model, whose dynamics includes the tidal shear, can produce a similar dependence. First, we explore the statistical correlation that originates from Gaussian initial conditions. We derive analytic expressions for a number of joint s...
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Analytic models based on spherical and ellipsoidal gravitational collapse have been used to derive the mass functions of dark matter halos and their progenitors (the conditional mass function). The ellipsoidal model generally provides a better match to simulation results, but there has been no simple analytic expression in this model for the conditional mass function that is accurate for small ...
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We use the physics of ellipsoidal collapse to model the probability distribution function of the smoothed dark matter density field in real and redshift space. We provide a simple approximation to the exact collapse model which shows clearly how the evolution can be thought of as a modification of the spherical evolution model as well as of the Zeldovich Approximation (Zel’Dovich 1970). In esse...
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ژورنال
عنوان ژورنال: The Astronomical Journal
سال: 2001
ISSN: 0004-6256
DOI: 10.1086/321137