Black hole accretion and host galaxies of obscured

Black hole accretion and host galaxies of obscured quasars Vincenzo Mainieri with Angela Bongiorno, Andrea Merloni & COSMOS

Introduction AGN-galaxies co-evolution M- relation: AGN and galaxies co-evolve (Magorrian et al. 1998; Gebhardt et al. 2000; Ferrarese & Merrit 2000; Tremaine et al. 2002) Hopkins+08 Vincenzo Mainieri (ESO) Hickox+09 QSO-2 and their host galaxies The X-ray Universe 2011

Introduction AGN-galaxies co-evolution Where the “food” is coming from? Secular processes Vincenzo Mainieri (ESO) Major mergers QSO-2 and their host galaxies The X-ray Universe 2011

QSO-2 sample Sample selection Selection criteria: LX>1044 erg s-1 NH>1022 cm-2 142 QSO-2 The galaxy to AGN contrast ratio is maximized: “easier” to study the morphology of the host as well as its stellar mass and SFR. Caveat: UV light can be contaminated from scattered AGN light, SFR diagnostics (e. g. H , [OII]) excited by accretion power rather than young stars, etc. . Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

X-ray properties Stacking Stacked X-ray spectrum • For the 34 QSO-2 with spectroscopic redshifts, only the rest-frame 2 -10 ke. V band was used for each spectrum. • Spectral binning was designed to match a fixed rest-frame 200 e. V intervals. • The total accumulated counts are 4763 NH=(5. 68. 33. 3)1022 cm-2 EW(Fe. K )~104� e. V See Poster G 41 (Salvato+11) Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

QSO-2 sample Redshifts Optical spectroscopy Dn(4000) = 1. 19± 0. 02 (Balogh+99) HδA = 4. 7± 0. 4 (Worthey&Ottaviani 97) Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

SED fitting : galaxy + AGN 14 Bands Used 6 SUBARU bands (U-z) I + K band (CFHT) 4 Spitzer/IRAC 24μm Spitzer/MIPS Vincenzo Mainieri (ESO) Galaxy templates: - 14 phenomenological: Polletta (2007) - Libr. of synthetic sp. (B&C) a) 10 declining SFH SFR µe-t/t t=[0. 1 -30] Gyr tage=[50 Myr-5 Gyr] tage<tuniv(z) 0 < E(B-V) <0. 5 b) 1 constant SF QSO-2 and their host galaxies AGN template: -Richards et al. (2006): mean QSO SED from 259 IRselected QSOs from the SDSS with Spitzer photometry 1<E(B-V)<9: <NH>~5 x 1022 cm-2 (assuming 1/3 of Galactic dust-to-gas) > E(B-V)~3 The X-ray Universe 2011

SED fitting : MIR/X-ray correlation Gandhi+09 VISIR/VLT high resolution imaging of a sample of local Seyferts: the least contaminated core fluxes • ~70 pc at z=0. 01 • <40% contaminating starformation in the unresolved flux A strong MIR (12. 3 m) / X-ray (2 -10 ke. V) correlation : log L 12. 3 m=(-4. 37± 3. 08)+(1. 106± 0. 071) log L 2 -10 ke. V Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

SED fitting : galaxy + AGN Chabrier IMF 2 minimization comparing observed and template fluxes at the redshift of the QSO -2 PRIORS • The maximum allowed age is the age of the Universe at the redshift of the source • The AGN SED should fit the 12. 3 m flux predicted using the Gandhi+09 correlation Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Stellar Mass • 80% of the hosts have M*>1010 Msun • the fraction increases with M* • Chabrier IMF • Ilbert+10: parent sample of ~70, 000 galaxies selected in the redshift range 0. 8 -1. 5, where there is a good completeness for M*> 5 x 109 Msun • We folded the parent sample with the X-ray sensitivity map Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Rest frame colors Host galaxies classification Photometric classification Separating red and blue galaxies (Wilmer+06): “Blue” QSO-2 : 42% “Red” QSO-2 : 58% Star formation activity classification Active: log(s. SFR/Gyr-1) > -1 (62%) Quiescent: log(s. SFR/Gyr-1) < -1 (38%) ~20% “red” hosts are dusty star-forming galaxies (see also Cardamone+10, Lusso+11) Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Star formation SFR-M* correlation • @ z~1 : 62% of the hosts are starforming and their rates are comparable to the main-sequence “Noeske” relation • Similar evolution of the <SSFR> Goal: compare the star formation in the QSO 2 hosts with the tight correlation between SFR and M* of blue star-forming galaxies (e. g. Noeske+07; Daddi+07; Elbaz+07; Pannella+09; Rodighiero+10). Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Star formation SFR-M* correlation • @ z~1 : 62% of the hosts are starforming and their rates are comparable to the main-sequence “Noeske” relation • Similar evolution of the <SSFR> Lutz, VM+10 Daddi+10 Mullaney+11 Daddi+10 Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Morphology Merging? • Greene et al. 2009 (SDSS QSO-2): nearly one-quarter have highly disturbed morphologies • Liu et al. 2009 (SDSS QSO-2): high fraction of double cores and physically associated companions from long-slit spectroscopy. Cisternas+11: a) no difference in the distortion fractions between inactive and active galaxies; b) ~65% of the AGN hosts are disk dominated. Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

Host galaxy properties Morphology 35 QSO-2 with z<1. 2 & IAB<24 ZEST+ (Scarlata+07; Carollo+11): Five non-parametric diagnostics (asymmetry A, F 775 W (i) F 160 W (H) concentration C, Gini coefficient G, 2 nd order moment of the brightest 20% of galaxy pixels M 20, ellipticity e) + Sersic index n Bulge-dominated Mergers Disks 23% 57% 20% Credits to the CANDELS team Lack of evidence is not necessarily evidence of lack: e. g. quasar phase at the end of the merging process (Di Matteo +05; Conselice 03)? Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011

QSO-2 sample Morphology and accretion rate • bulge dominated galaxies tend to host low Edd ratios BHs • disks and mergers host high Edd ratios BHs mass BHs are the fastest accretors (e. g Mc. Lure & Dunlop 2002; Netzer & Trakhtenbrot 2007) <MBH>~4 x 108 Msun • lowest Vincenzo Mainieri (ESO) <MBH>~1 x 108 Msun QSO-2 and their host galaxies The X-ray Universe 2011

Conclusions • Type-2 QSOs reside almost exclusively in massive galaxies, 80% have M*>1010 MSUN and the fraction of galaxies hosting them monotonically increases with M* • The majority of the hosts (>60%) are actively forming stars • The SSFR of QSO-2 hosts is similar to what observed for star-forming (“Noeske”) galaxies at z~1. • The evolution of SSFR of QSO-2 hosts is similar to the one of SFGs. • � Morphological analysis suggests that the majority of the hosts are bulge dominated. • We do not find clear signature of merger activity for the majority of the hosts but it could be a time issue: QSO phase at the end of a major merger event. Difficult to test the quasar fueling models by studying the morphology. Vincenzo Mainieri (ESO) QSO-2 and their host galaxies The X-ray Universe 2011