THE MODERATELY LARGE SCALE STRUCTURE OF QUASARS

Jari Kotilainen (Tuorla Observatory)

High z quasars: lighthouses of sites of galaxy formation

quasar space density vs BH growth rate vs SFR history=> mergers trigger both SF and quasar activity? => rapid decline of BH activity at low z

Merloni et al. 2005

HIGH Z QUASARS AND GALAXY FORMATION

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)

nearby quasar hosts: massive bulge-dominated galaxies

masers gas stars

The most distant quasar (z = 6.4): molecular gas, dust, SF, metals and BH

Barth et al. 2003

How did massive bulges and SMBHs form in < 1 Gyr?

QUASAR HOSTS AT HIGH REDSHIFT (z > 1)

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)

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

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 ?

RLQ

RQQ

… where BHs are fuelled and galaxies grow by mergers

=> predict decrease in host luminosity

=> NOT observed up to z = 2

c.f. hierarchical structure formation…

more recent models: AGN/SN feedback

Granato et al. 2004, Bower et al. 2006

Di Matteo et al. 2005

WORK IN PROGRESS...

evolution of MBH

– Mbulge

relation with z?

spectra of resolved quasars at 1 < z < 3

images => Mbulge spectra => virial MBH

z = 1.8z = 2.5

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

MORE WORK IN PROGRESS...

Falomo et al. 2005

...but no radio luminosity dependence of clustering/DM content/BH mass

Magliocchetti et al. 2005

also: lensing, close companions...