The Void Phenomenon Explained (Tinker Conroy, computer sims)

  • Thread starter marcus
  • Start date
marcus
Science Advisor
Gold Member
Dearly Missed
24,712
783

Main Question or Discussion Point

http://arxiv.org/abs/0804.2475
The Void Phenomenon Explained
Jeremy L. Tinker (KICP, UChicago), Charlie Conroy (Princeton)
8 pages, 5 figures, submitted to ApJ
(Submitted on 16 Apr 2008)

"We use high-resolution N-body simulations, combined with a halo occupation model of galaxy bias, to investigate voids in the galaxy distribution. Our goal is to address the 'void phenomenon' of Peebles (2001), which presents the observed dearth of faint galaxies in voids as a challenge to the current cosmology. In our model, galaxy luminosity is determined only as a function of dark matter halo mass. With this simple assumption, we demonstrate that large, empty voids of ~15 Mpc/h in diameter are expected even for galaxies seven magnitudes fainter than L*. The predictions of our model are in excellent agreement with several statistical measures; (i) the luminosity function of galaxies in underdense regions, (ii) nearest neighbor statistics of dwarf galaxies, (iii) the void probability function of faint galaxies. In the transition between filaments and voids in the dark matter, the halo mass function changes abruptly, causing the maximum galaxy luminosity to decrease by ~5 magnitudes over a range of ~1 Mpc/h. Thus the boundary between filaments and voids in the galaxy distribution is nearly as sharp for dwarfs as for ~L* objects. These results support a picture in which galaxy formation is driven predominantly by the mass of the host dark matter halo, and is nearly independent of the larger-scale halo environment. Further, they demonstrate that LCDM, combined with a straightforward bias model, naturally explains the existence of the void phenomenon."
 

Answers and Replies

Related Threads for: The Void Phenomenon Explained (Tinker Conroy, computer sims)

  • Last Post
Replies
8
Views
3K
  • Last Post
Replies
6
Views
774
  • Last Post
Replies
7
Views
8K
  • Last Post
2
Replies
34
Views
8K
Replies
16
Views
4K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
16
Views
1K
  • Last Post
Replies
3
Views
5K
Top