Jari Kotilainen (Tuorla Observatory) THE MODERATELY LARGE SCALE STRUCTURE OF QUASARS
HIGH Z QUASARS AND GALAXY FORMATION High z quasars: lighthouses of sites of galaxy formation quasar space density vsBH growth ratevs SFR history => mergers trigger both SF and quasar activity? => rapid decline of BH activity at low z Merloni et al. 2005
BHs in all (?) local massive bulges Milky Way: M ~3 x 106 Msun => all massive galaxies host a remnant BH from a quasar phase?
Kormendy 2004 tight MBH – Mbulge – σbulge correlations (at low z) masersgasstars nearby quasar hosts: massive bulge-dominated galaxies
The most distant quasar (z = 6.4): molecular gas, dust, SF, metals and BH Barth et al. 2003 How did massivebulgesandSMBHs form in < 1 Gyr?
VLT + ISAAC non-AO imaging => 30 hosts at 1 < z < 2 VLT+NACO AO imaging => two RLQ hosts (z ~2.5 and z ~2.9) two RQQ hosts (z ~2.1 and z ~2.5) QUASAR HOSTS AT HIGH REDSHIFT (z > 1) Kotilainen et al. 2007 ApJ 660, 1039 Falomo et al. 2007 ApJ, in press
Evolution of quasar host luminosity RLQ hosts ~10 x more luminous (massive) BH mass? mass accretion rate? BH mass threshold for radio activity? c.f. clustering properties, SEDs RLQ passive evolution into local massive spheroids no decrease in luminosity ? => early epoch for the latest merger decrease in luminosity ? => tight quasar - host co-evolution different for RLQs and RQQs ? RQQ
c.f. hierarchical structure formation… … where BHs are fuelled and galaxies grow by mergers => predict decrease in host luminosity => NOT observed up to z = 2 Di Matteo et al. 2005 more recent models: AGN/SN feedback Granato et al. 2004, Bower et al. 2006
WORK IN PROGRESS... evolution of MBH –Mbulgerelation with z? spectra of resolved quasars at 1 < z < 3 images => Mbulgespectra => virialMBH z = 1.8 z = 2.5
MORE WORK IN PROGRESS... CDM => massive density peaks in early Universe are strongly clustered: cores of rich clusters => clustering of high z quasars for radio galaxies: threshold DM halo (BH) mass required to produce significant radio emission... Magliocchetti et al. 2005
...but no radio luminosity dependence of clustering/DM content/BH mass Magliocchetti et al. 2005 also: lensing, close companions... Falomo et al. 2005