Properties of High Redshift Quasars-I: Evolution of the super-massive black-hole to halo mass ratio

Abstract

In the local universe, the masses of Super-Massive Black-Holes (SMBH) appear to correlate with physical properties of their hosts, including the mass of the dark-matter halos. At higher redshifts, we observe the growth of SMBHs indirectly through identification of high redshift quasars. However information on their hosts is difficult to obtain. In this paper we determine the masses of halos that host high redshift quasars (at z>4) by comparing the rate of growth of quasar density with that predicted by the Press-Schechter mass function. The host mass determined depends on how the ratio between SMBH and host halo mass evolves with redshift. Assuming the ratio between SMBH and halo mass does not evolve with redshift, we find a host halo mass of log(M)=11.7+/-0.3 solar masses. Even if the quasars shine at their Eddington limit, this mass is significantly smaller than that seen in the local universe. Indeed the null-hypothesis, of a constant SMBH to halo mass ratio at all redshifts, can be ruled out at greater than a 5-sigma level. SMBHs must therefore have contributed a larger fraction to the host mass in the past. Including redshift evolution of the SMBH to halo mass ratio, we find larger halo masses of log(M)=12.4+/-0.3 solar masses, and a ratio between SMBH and halo mass that increases with redshift as ~(1+z)^1.5 are required to be consistent with both local and high redshift observations. We investigate restrictions placed on the critical linear overdensity of quasar hosts at their epoch of virialisation and find that it cannot exceed the traditional value of delta_c=1.69 by more than a factor of two. Finally, we find that the high redshift quasars are hosted by fluctuations on scales that have a variance of (delta M/M) = 2-3, corresponding to (3-4.5)-sigma fluctuations in the density field.

arXiv comment8 pages, 7 figures, submitted to MNRAS

References in corpus (26)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• A Universal Density Profile from Hierarchical Clustering
• The slope of the black-hole mass versus velocity dispersion correlation
• Mass function of dark matter halos
• A Unified Model for the Evolution of Galaxies and Quasars
• The Assembly and Merging History of Supermassive Black Holes in Hierarchical Models of Galaxy Formation
• An excursion set model of hierarchical clustering: Ellipsoidal collapse and the moving barrier
• A Survey of z>5.8 Quasars in the Sloan Digital Sky Survey I: Discovery of Three New Quasars and the Spatial Density of Luminous Quasars at z~6
• Observational constraints on growth of massive black holes
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey II: Discovery of Three Additional Quasars at z>6
• Beyond the Bulge: a Fundamental Relation Between Supermassive Black Holes and Dark Matter Halos
• The M(BH)-Sigma Relation for Supermassive Black Holes
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey IV: Discovery of Seven Additional Quasars
• Self-Regulated Growth of Supermassive Black Holes in Galaxies as the Origin of the Optical and X-ray Luminosity Functions of Quasars
• High-Redshift Quasars Found in Sloan Digital Sky Survey Commissioning Data IV: Luminosity Function from the Fall Equatorial Stripe Sampl
• A Survey of z>5.7 Quasars in the Sloan Digital Sky Survey III: Discovery of Five Additional Quasars
• Quasar Clustering and the Lifetime of Quasars
• Quasar Feedback: the Missing Link in Structure Formation
• A 3x10^9 solar mass black hole in the quasar SDSS J1148+5251 at z=6.41
• Observational Signatures of the First Quasars
• High-excitation CO in a quasar host galaxy at z=6.42
• Constraining the Lifetime of Quasars from their Spatial Clustering
• Constraints on galaxy halo profiles from galaxy-galaxy lensing and Tully-Fisher/fundamental plane relations
• Spectral Signature of Cosmological Infall of Gas Around the First Quasars
• Nonlinear density evolution from an improved spherical collapse model
• Gemini imaging of QSO host galaxies at z~2

Cited by in corpus (12)

• Clustering of Low-Redshift (z <= 2.2) Quasars from the Sloan Digital Sky Survey
• The 2dF-SDSS LRG and QSO Survey: QSO clustering and the L-z degeneracy
• Growing the first bright quasars in cosmological simulations of structure formation
• A simple model to link the properties of quasars to the properties of dark matter halos out to high redshift
• Evolution of high-redshift quasar hosts and promotion of massive black hole seed formation
• On the Prevalence of Super-Massive Black Holes over Cosmic Time
• Constraining quasar host halo masses with the strength of nearby Lyman-alpha forest absorption
• Probing the environment of high-z quasars using the proximity effect in projected quasar pairs
• Source Mergers and Bubble Growth During Reionization
• SMBH growth parameters in the early Universe of Millennium and Millennium-II simulations
• Redshifted 21cm Observations of High Redshift Quasar Proximity Zones
• A semi-analytical perspective on massive red galaxies: I. Assembly history, environment & redshift evolution