Redshift distribution of quasars and initial spectrum of small-scale fluctuations.
Abstract
The authors study the dependence of the number density of bright quasars at different redshifts nQSO(z) on the initial power spectrum P(k). QSOs are assumed to be a short early stage in the evolution of massive galaxies with M ≥ 2×1011Msun. The percentage α of galaxies at this stage, the stage beginning and duration are determined by minimizing the divergence between the theoretical space distribution of QSOs for a specified initial spectrum and the observed distribution, The best fit is obtained with the redshift distribution of QSOs for the tilted cold-dark-matter (CDM) model with Ωb = 0.1, n = 0.7 and for the QSO stage which lasts for about 4×105/α years, beginning 108years after the moment when first counterflows arise in the collisionless component and a shock wave arises in the gas. The authors consider a possibility to reconstruct the initial power spectrum on small scales from the observed redshift distribution of QSOs. When compared to the standard CDM model, such a spectrum is found to have a lower power at 1 ≤ k ≤ 10 h Mpc-1 and a bump at k > 10 h Mpc-1. Observational consequences of such behavior of the spectrum on small scales are analyzed.
- Publication:
-
Kinematics and Physics of Celestial Bodies
- Pub Date:
- January 1996
- Bibcode:
- 1996KPCB...12b..25N
- Keywords:
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- Universe: Galaxy Distribution;
- Universe: Galaxy Evolution;
- Redshifts: Quasars