The multiwavelength surveys of the ELAIS-S1 and GOODS fields Fabrizio Fiore & M. Brusa, A. Comastri, C. Feruglio, A. Fontana, A. Grazian, F. La Franca, P. Santini, E. Piconcelli, S. Puccetti and many others

GOAL AGN Bolometric Luminosity function Complete SMBH census Strong constraints to models for the formation and evolution of structure in the Universe

Co-evolution of galaxies and SMBH Two seminal results: 1.The discovery of SMBH in the most local bulges; steep and tight correlation between M BH and bulge properties. 2.The BH mass density obtained integrating the AGN L.-F. and the CXB = that obtained from local bulges  most BH mass accreted during luminous AGN phases! Most bulges passed a phase of activity: Need to understand AGN physics and evolution to fully understand galaxy evolution

Why multiwavelength surveys X-ray surveys: very efficient in selecting unobscured and moderately obscured AGN Miss most highly obscured AGN La Franca et al. 2005

2-10 keV AGN luminosity function models LDDE with constant N H distribution La Franca et al Solid = observed dashed = best fit

Highly obscured Mildly Compton thick INTEGRAL survey ~ 100 AGN Sazonov et al. 2006

2-10 keV AGN luminosity function models LDDE with variable absorbed AGN fraction La Franca et al. 2005, see the poster by Fabio La Franca 2-10keV 0.5-2keV

A working scenario small mass progenitors. Feedback is effective in self-regulating accretion and SF, cold gas is left available large mass progenitors. Feedback is less effective, most gas is quickly converted in stars at high z. Galactic cold gas available for accretion and obscuration increases at high z Menci hierarchical clustering model, Menci, Puccetti Fiore 2006

1) Paucity of Seyfert like z>1 is real? Or, is it, at least partly, a selection effect? Are we missing in Chandra and XMM surveys highly obscured (N H  cm -2 ) AGN? Which are common in the local Universe…

Why multiwavelength surveys IR surveys: AGNs even highly obscured at optical and X-ray energies shine in the MIR Very difficult to isolate AGN from passive and starforming galaxies (Lacy 2004, Barnby 2005, Stern 2005, Polletta 2006 and many others) Polletta et al. 2006

Use both X-ray and MIR surveys: Select unobscured and moderately obscured AGN in X-rays Add highly obscured AGNs selected in the MIR Simple approach: Differences are emphasized in a wide-band SED analysis Why multiwavelength surveys

X-ray-MIR surveys CDFS-Goods MUSIC catalog (Grazian et al. 2006). Area 0.04 deg 2  173 X-ray sources, keV down to 3  cgs, 109 spectroscopic redshifts  4300 MIPS sources down to 6.8  Jy, 3.6  m detection down to 0.08  Jy  Ultradeep Optical/NIR photometry, R~27.5, K~24 ELAIS-S1 SWIRE/XMM/Chandra survey (Puccetti et al. 2006, Feruglio et al. 2006). Area 0.5 deg 2  500 sources, keV down to 3  cgs, half with spectroscopic redshifts.  2600 MIPS sources down to 100  Jy, 3.6  m detection down to 6  Jy  Relatively deep Optical/NIR photometry, R~25, K~19 In future we will add: COSMOS XMM/Chandra/Spitzer. Area 2 deg 2 see Marcella talk CDFN-Goods. Area 0.04 deg 2 Etc.

MIR selection CDFS obs. AGN ELAIS-S1 obs. AGN GOODS 24  m galaxies ELAIS-S1 24  m galaxies Open symbols = unobscured AGN Filled symbols = optically obscured AGN

MIR selection CDFS obs. AGN ELAIS-S1 obs. AGN GOODS 24  m galaxies

MIR AGNs

F24  m/FR >1000 R-K>4.5 F( keV)~ cgs F(1.5-4keV)~ cgs

F24  m/FR >1000 R-K> sources (3% of the MIPS sample) 17 detected by Chandra ( keV band) 4 more visible in the image =43.45+/- 0.24, =22.9+/-0.8, ~2.1 logF(1.5-4keV) stacked logL obs (2-8keV) stacked sources ~41.8 log ~44.6 ==> logL(2-8keV) unabs.~43 Difference implies logN H  24 ~400!! Msun/yr ~5!! Msun/yr ~65 Msun/yr

F24  m/FR >1000 R-K>4.5

F24  m/FR 4.5 F( keV)~2  cgs F(1.5-4 keV) < 5  cgs

F24  m/FR sources (3% of the MIPS sample) 29 detected by Chandra, keV, =43.4+/-0.4 =23.2+/-0.6, ~1.4 ~ 8 Msun/yr ~ 2.6 Msun/yr ~20 Msun/yr

Summary XMM & Chandra surveys can probe unobscured and moderately obscured accretion up to z=2-4 INTEGRAL/Swift find highly obscured AGN up to z~0.1 Spitzer finds highly obscured AGN at z~1-3 Herschel will further increase the band, so helping in separating AGN from normal galaxies and pushing toward higher z. During the next decade highly obscured AGN will be confirmed and studied in detail using hard X-ray focusing telescopes. All this will allow a precise determination of the evolution of the accretion in the Universe and a precise census of accreting SMBH.

MIR selected vs. X-ray selected AGNs