The Dark Side of QSO Formation at High Redshifts

Details The Dark Side of QSO Formation at High Redshifts The Dark Side of QSO Formation at High Redshifts

2010-10-18

arxiv.org/abs/1010.3715v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

12 pages, 7 figures, revised after the referee comments, to be published by the Astrophysical Journal

Scientific paper

Observed high-redshift QSOs, at z~6, may reside in massive dark matter (DM) halos of more than 10^{12} Msun and are thus expected to be surrounded by overdense regions. In a series of 10 constrained simulations, we have tested the environment of such QSOs. Comparing the computed overdensities with respect to the unconstrained simulations of regions empty of QSOs, assuming there is no bias between the DM and baryon distributions, and invoking an observationally-constrained duty-cycle for Lyman Break Galaxies, we have obtained the galaxy count number for the QSO environment. We find that a clear discrepancy exists between the computed and observed galaxy counts in the Kim et al. (2009) samples. Our simulations predict that on average eight z~6 galaxies per QSO field should have been observed, while Kim et al. detect on average four galaxies per QSO field compared to an average of three galaxies in a control sample (GOODS fields). While we cannot rule out a small number statistics for the observed fields to high confidence, the discrepancy suggests that galaxy formation in the QSO neighborhood proceeds differently than in the field. We also find that QSO halos are the most massive of the simulated volume at z~6 but this is no longer true at z~3. This implies that QSO halos, even in the case they are the most massive ones at high redshifts, do not evolve into most massive galaxy clusters at z=0.

Affiliated with

Also associated with

No associations

Rating

The Dark Side of QSO Formation at High Redshifts 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 The Dark Side of QSO Formation at High Redshifts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Dark Side of QSO Formation at High Redshifts will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-267489