1. Obscured AGN in the (z)COSMOS survey AGN9, Ferrara, May 25 2010 Angela Bongiorno Max-Planck-Institut für extraterrestrische Physik, Garching, GERMANY AND Andrea Merloni Marco Mignoli Gianni Zamorani Marcella Brusa And The COSMOS/zCOSMOS teams

2.  Complete census of AGN (in particular obscured population)  How obscured AGN evolve  Fraction of obscured AGN (as a function of e.g. L and z) Hierarchical growth Growth of SMBH Gas inflow AGN feedback Active Quasar Starburst & buried Quasar Normal galaxies Galaxy mergers (adapted from Hopkins et al., 2008)

3. THE COSMIC EVOLUTION SURVEY 2 deg 2 equatorial HST treasury project Deep: ACS i AB < 27 Multi-wavelength observations Similar volume as SDSS, but fainter and higher z 19-band photo-z RA = 10:00:28.6 Dec = +02:12:21

4. Multi-wavelength Data: XMMHST Spitzer Subaru VLA  VLA 1.4 GHz – 7 μJy  Spitzer-IRAC 3-8 μm – 10 μJy  Spitzer-MIPS 24 µm – 15 mJy  HST-ACS – i AB ~27  Subaru Bvriz – m AB ~27  GALEX N/F UV – m AB ~26  XMM 0.5-10 keV – 10 -15 cgs  Chandra 0.5-2 keV -- 2x10 -16 cgs Chandra

5. SPECTRA: the z-COSMOS project  600 hrs of observation with VIMOS on VLT started April 2005  Spectra will be obtained for: ~20,000 galaxies at 0.3 < z < 1.0 selected to have I AB <22.5 (BRIGHT SAMPLE) ~10,000 galaxies at 1.4 < z <2.5 with B AB <25 and chosen by color- selection criteria (DEEP SAMPLE) Extra targets from XMM, GALEX and radio catalogue VIMOS @VLT P.I. S. Lilly zCOSMOS Institutes ETH Zurich LAM Marseille LAOMP Toulouse INAF Milano INAF Bologna MPE Garching VIMOS @VLT

6. [OIII] Line Luminosity Function I Comparison with other surveys SDSS type2 (Reyes+08) local LF SDSS (Hao+05 ) XLF XMM-HBS (DellaCeca+08) COSMOS X-ray LF (Bongiorno, Mignoli, Zamorani et al., 2010 A&A 510, 56B) Luminosity-dependent density evolution (LDDE)  1=2.13  2=0.5 L*=1.1 10 41  *=2.55 10 -5

7. Fraction of type-2 AGN 0.15 < z < 0.3 from ∼ 65% to ∼ 50% from L [O III ] = 10 6.2 -10 8.2 L  to 10 8. 2 -10 9. 2 L  at L [OIII] > Lc, decreasing fraction of type–2 AGN with luminosity What happen at L [OIII] < Lc? 0.3 < z < 0.45 and 0.5 < z < 0.92 from ∼ 80% to ∼ 25% from L [O III =10 6.2 -10 8.5 L ⊙ to L [O III] =10 9.0 -10 9.6 L ⊙ (Bongiorno, Mignoli, Zamorani et al., 2010 A&A 510, 56B) SDSS (Reyes08) zCOSMOS

8. SDSS type-2 AGN sample @z<0.3 (Kauffmann & Heckman 2008) BH accretion as a function of galaxy properties… Feast : Galaxies rich in cold gas ; BH growth is regulated by small-scale feedback. Famine: Galaxies poor in cold gas. BH accretes ~0.3% - 1% of the mass lost by evolved bulge stars. ~2% Edd Eddington  Log(L[OIII]/M BH ) =1.7

9. BH accretion and star formation… at higher redshift using the 20k zCOSMOS type-2 AGN sample  392 sources @ z~1 (close to the peak of the cosmic AGN and star formation density) ➤ AGN hosts masses through SED fitting AGN templates: - Elvis et al. (1994) - E(b-v)=0 - 0.3 in 0.01 steps Galaxy templates: - 14 phenomenological from Polletta (2007) - Libr. of synthetic sp. (Bruzual & Charlot) a) 10 declining SFH SFR  e -t/   =[0.1-30] Gyr t age =[50Myr-5 Gyr] t age <t univ (z) 0 < E(B-V) <0.5 b) 1 constant SF Separate the Spectral Energy Distribution of AGN into nuclear+host components and derive the host properties (Merloni, Bongiorno et al. 2010 ApJ 708, 137M) Red/Purple: Galaxy template Blue: AGN template Used Bands 6 SUBARU bands K band (CFHT) 4 Spitzer/IRAC 24  m Spitzer/MIPS

10. SED fitting  M*  (scaling relation)  BH masses (150) ~1.5%Edd ~0.2%Edd ( Bongiorno, Merloni et al. in prep) BH accretion and star formation… at higher redshift ➤ Computation of the BH Masses

11. ( Bongiorno, Merloni et al. in prep) ~0.6%Edd ~0.02%Edd Using the sSFR to distinguish “old” and “young” galaxies (391)

12. ( Bongiorno, Merloni et al. in prep) Using the sSFR to distinguish “old” and “young” galaxies Dotted lines: [OIII] completeness limit Gradual trend towards lower Eddington ratios with older stellar population content. However … selection effect still to be fully accounted for… Hopkins & Hernquist (2008): The bimodality comes from the evolution of the triggering rates (mergers) in combination with a luminosity dependent AGN lifetimes.