Obscured and unobscured growth of Super-massive Black Holes from the XMM-Newton Medium Survey Francisco J. Carrera, X. Barcons, J. Bussons, J. Ebrero, M. Ceballos, A. Corral (IFCA, CSIC-UC, Spain) and many SSC colleagues SSC#20, Potsdam, Nov. 13, 2006

Definition of the AXIS survey Carrera et al XMM-Newton target fields: –Galactic latitude |b|>20 deg –X-ray observations with EPIC-pn detector in FULL-FRAME-MODE –~Avoided fields with bright and/or extended targets –Good time intervals > 10 ksec –Available early on in the mission Areas around target + OOT+ near the pn CCD gaps excluded Solid angle ~4.8 deg 2 Using SAS v6.1.1 to produce final source list and products: –Exposure and background maps –Source detection –Spectra and calibration matrices Own empirical sentitivity maps from detected source parameters Very detailed source screening Total of 1433 distinct X-ray sources with detection likelihood >15 in any of 4 bands (see below) NGC4291 Mrk 205

Soft keV XID keV Hard 2-10 keV Ultrahard keV X-ray source counts ( BSS/HBS Della Ceca et al & CDF Bauer et al & AMSS Ueda et al )

The contribution to the X-ray background Shallow MediumDeep Surveys Medium surveys resolve the brightest 50% of the X-ray background Soft Hard XID Ultra-hard

Detected significant (>99%) clustering in soft/XID: –In whole sky No clustering in hard/ultrahard: because not enough sources? No clustering in hard-spectrum sources Angular clustering

The XMS samples Barcons et al. 07 NameBand (keV)Flux limit cgs # sources (unique) # identified (fraction) Soft XMS-S (1)200 (95%) Hard XMS-H (20)132 (83%) XID XMS-X (56)261 (92%) Ultrahard XMS-U (2)60 (86%) Subset of AXIS: –25 fields chosen for follow-up: 3.3 deg 2 –Flux limited in Soft, Hard and XID: total of 318 sources

Optical identification of the XMS Optical imaging: g,r,i (SDSS), Z (Gunn), mostly at the INT/WFC to r~23-24 mag Reliable & unique candidate counterpart in r/i for virtually all sources (< 5” or < 5  ): only 5 “empties” Optical spectroscopy –50% from AXIS programme (WHT, TNG, NOT): multi-fibre and long-slit spectroscopy –20% from Calar Alto/3.5m long-slit spectroscopy –15% from VLT/FORS2 long-slit spectroscopy –A few from AAT/2dF, SUBARU/FOCAS, SAO and others

4m spec lim 10m spec lim Deep MediumShallow Full sample

Breakdown of identified sources XMS-S Soft XMS-H Hard XMS-X XID XMS-U Ultrahard Broad-line AGN75% (148/200) 63% (83/132) 73% (190/261) 65% (39/60) Narrow-line galaxies (AGN) 13% (27/200) 27% (35/132) 15% (39/261) 27% (16/60) Absorption line galaxies+clust 4% (8/200) 7% (9/132) 4% (10/261) 5% (3/60) Stars8% (15/200) 2% (3/132) 8% (20/261) 0% (0/60)

Redshift distribution Peak of QSO distribution (z~1.5) well sampled. Obscured population out to z~1 in Hard sample Soft Hard z z # #

Luminosities and redshifts Soft z=2.2 QSOs “Seyferts” z z All galaxies consistent with hosting AGN L X >10 42 erg/s: obscured AGN log(L Soft cgs) log(L Hard cgs) Hard

(Preliminary) X-ray spectral analysis Extracted X-ray spectra (pn+MOS) for all 318 sources Fitted Gal. abs. * power law Fitted Gal. abs. * Intrinsic abs. * power law F-test 95%: X-ray absorbed 72  Filled symbols –12 BLAGN –17 NELG –5 Gal NHNH z Full sample

16/35 unidentified sources X-ray absorbed (obscured AGN?) Full sample (Preliminary) X-ray spectral analysis

Procedure still being tested Selecting X-ray spectra with >80cts Unfolding with best fit Galactic+Intrinsic absorption power law De-absorbing (correcting for Galactic N H ) De-redshifting Renormalizing using flux in 2-8 keV band Averaging in final bins (≥500 cts) Averaging AXIS: –BLAGN (200 sources) –NELG (43) Much improved averaging AXIS+XMM-2dF: –BLAGN (549):  =1.95±0.02 Fe keV EW=130±60 eV: ~3  –NELG (113):  =1.53±0.02 Fe keV EW=130±100 eV: <~2  Averaging X-ray spectra Corral et al., in preparation AXIS+XMM-2dF BLAGN AXIS+XMM-2dF NELGs

Procedure still being tested Selecting X-ray spectra with >80cts Unfolding with best fit Galactic+Intrinsic absorption power law De-absorbing (correcting for Galactic N H ) De-redshifting Renormalizing using flux in 2-8 keV band Averaging in final bins (≥500 cts) Averaging AXIS: –BLAGN (200 sources) –NELG (43) Much improved averaging AXIS+XMM-2dF: –BLAGN (549):  =1.95±0.02 Fe keV EW=130±60 eV: ~3  –NELG (113):  =1.53±0.02 Fe keV EW=130±100 eV: <~2  AXIS+XMM-2dF BLAGN AXIS+XMM-2dF NELGs Averaging X-ray spectra Corral et al., in preparation

Tips for statistical identification ~90% Obscured AGN (most Xabs) 90% unobscured AGN Stars HR 2 log(F Hard /F opt ) Full sample

X-ray to optical ratio: a marker for obscuration? Soft 5% of sources with F X /F opt >10 ≥40% of F X /F opt >10 obscured AGN F X /F opt >10 Hard log(F Hard /F opt ) 15% of sources with F X /F opt >10 ~70% of F X /F opt >10 obscured AGN log(F Soft /F opt ) F X ( cgs)

Optical colours QSOs S+Irr E+S0 10% of QSOs are red QSOs S+Irr E+S0 HardSoft r-i g-r #

Optical versus X-ray “colours”: Hard Hard Softer Harder sources are >90% obscured AGN Softer sources: Optically blue: unabsorbed AGN Optically red: mix of abs & unabs AGN HR 2 g-r Redder

On-going work Brightest 50% of the X-ray background dominated by AGN. Unobscured accretion dominates, but increasingly important contribution from obscured objects. X-ray absorption and optical obscuration not equivalent: –10% of type 1 AGN are X-ray absorbed –15% of type 2 AGN are not X-ray absorbed –25% of F X /F opt >10 hard X-ray sources are type 1 AGN –10% of X-ray selected type 1 AGN have red colours Even at medium fluxes, an important fraction of the X-ray sources have optically faint and red optical counterparts: –Need 10m class observing time Most unIDed objects faint (r/i>21.5) and Xabs: NELGs? Results from average spectra show Fe lines in both BLAGN and NELGs

Publications Carrera et al (submitted): X-ray catalogue of AXIS sources –logN-logS –angular correlation –Answer from the referee ~OK: expected re-submission by end of year Corral et al (in prep.): spectral stacking analysis of AXIS and XMS sources (+2dF?) Barcons et al. ~2007: XMS IDs and col-col plots Ebrero et al. ~2007: luminosity function Bussons et al. ~2007: SEDs ?? et al. ~2007: statistical IDs with 2dF?

Observing proposals Submitted: –SAO/6m 6 nights March: XMS/UH mag>21.5 –CAHA/3.5m Omega2000: wide-field IR im. –XMM: deep look (200ks) at 4 Compton-thick candidates Planned: –CAHA/3.5m Omega2000: wide-field/QSO2 IR im. –VLT/VIMOS LBQS2212?: MOS spectroscopy