The Real and Redshift Space Density Distribution Function for Large-Scale Structure in the Spherical Collapse Approximation
نویسندگان
چکیده
We use the spherical collapse (SC) approximation to derive expressions for the smoothed redshift-space probability distribution function (PDF), as well as the porder hierarchical amplitudes Sp, in both real and redshift space. We compare our results with numerical simulations, focusing on the Ω = 1 standard CDM model, where redshift distortions are strongest. We find good agreement between the SC predictions and the numerical PDF in real space even for σL ∼ > 1, where σL is the linearly-evolved rms fluctuation on the smoothing scale. In redshift space, reasonable agreement is possible only for σL ∼< 0.4. Numerical simulations also yield a simple empirical relation between the real-space PDF and redshift-space PDF: we find that for σ ∼ < 1, the redshift space PDF, P [
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