Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach

Details Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach

2002-10-23

arxiv.org/abs/astro-ph/0210507v1

Mon.Not.Roy.Astron.Soc. 339 (2003) 495

Astronomy and Astrophysics

Astrophysics

13 pages, 7 figures, accepted for publication in MNRAS

Scientific paper

10.1046/j.1365-8711.2003.06199.x

We present a simple model based on the dark halo approach which provides a useful way to understand key points determining the shape of the non-Gaussian tails of the dark matter one-point probability distribution function(PDF). In particular, using the scale-free models with power-law profile of dark halos, we derive a simple analytic expression for the one-point PDF. It is found that the shape of the PDF changes at the characteristic value of $\delta_*$ which is defined by the smoothed density of a halo with the characteristic mass $M_*$ at the epoch. In cold dark matter models with top-hat smoothing filters, the characteristic smoothed density at present time typically takes the value $\delta_*\gg 1$ for a small smoothing scale $\rth\sim 1$Mpc$/h$ and conversely $\delta_*\ll 1$ for a large smoothing scale $\rth > 10$Mpc$/h$. On the range $\delta/\delta_*<1$, the shape of the PDF is almost solely determined by the outer slope of halos and scales as a power-law. The resultant non-Gaussian tails of PDF then resemble the log-normal PDFs in that range and show a good agreement with N-body simulations, which can be ascribed to the universality of the outer slope of the halo profile. In contrast, tails of one-point PDF in the range $\delta/\delta_*>1$ basically follow the steep exponential tails of the halo mass function, which exhibit a strong sensitivity to both the outer slope of the halo profile and the initial power spectrum. Based on these results, the discussion on the PDF of galaxy distribution and the application to the weak lensing statistics are also presented.

Affiliated with

Also associated with

No associations

Rating

Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-Gaussian Tails of Cosmological Density Distribution Function from Dark Halo Approach will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-639875