# Distribution of dark matter

1. May 3, 2014

### Lapidus

How is dark matter distributed (as far as we know)?

Let's stay with a single galaxy like the Milky Way. I heard that dark matter is even more concentrated in the center than in the halo, that it is falling off when moving outside, but since the halo is so huge (how huge, ten times larger?) most dark matter can be found there. Is that correct?

So there is dark matter also in our solar system. But by what density? If the density would be high, we would have noticed it by the motion of the planets or nearby stars. Can the effect of dark matter only be seen at larger distances where it accumulates despite its low density?

thanks!

2. May 3, 2014

### phyzguy

What you said is largely correct. There's lots of work to understand the Milky Way dark matter halo. One model (see this paper) is a density profile like:
$$\rho_{DM} = \rho_0 (r/r_s)^{-\gamma} (1+r/r_s)^{-3+\gamma}$$

with gamma = 1.24, rs = 28.1 kpc, and rho0 = 3.5E-3 Msun/pc^3.

3. May 3, 2014

### Lapidus

Yes, that answers my question, thanks!!

4. May 5, 2014

### Lapidus

Btw, does anybody know a great review/ overview article (or a book or sections of a book) about dark matter? One that is not complete layman but not complete specialist either.

thanks!!

5. May 6, 2014

### Mordred

my signature contains numerous article that have sections covering dark matter. Most articles directly related to DM are related to distributions, properties etc of specific proposals and models. the misconceptions section on the http://cosmology101.wikidot.com/main signature link has one decent non technical article with a dark matter section. The articles on the site are primarily geared to helping teach modern cosmology. In particular the FLRW metrics etc. There are some textbook style articles on cosmology that include DM modelling.

http://arxiv.org/abs/1304.4446 :"What we have leaned from Observational Cosmology." -A handy write up on observational cosmology in accordance with the LambdaCDM model

you can also browse www.arxiv.com however keep in mind what I stated above, concerning the numerous alternate proposals.