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 06 • 36 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 deg2

• 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

Soft0.5-2 keV

XID0.5-4.5

keV

Hard2-10 keV

Ultrahard4.5-7.5 keV

X-ray source counts (BSS/HBS Della Ceca et al. 2004 & CDF Bauer et al. 2004 & AMSS Ueda et al. 2005)

The contribution to the X-ray background

ShallowMediumDeep Surveys

Medium surveysresolve the

brightest50% of the

X-raybackground

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

Name Band (keV)

Flux limit 10-14 cgs

# sources(unique)

# identified (fraction)

Soft XMS-S

0.5-2 1.5 210 (1) 200 (95%)

Hard XMS-H

2-10 3.3 159 (20) 132 (83%)

XID XMS-X

0.5-4.5 2.0 284 (56) 261 (92%)

Ultrahard XMS-U

4.5-7.5 - 70 (2) 60 (86%)

• Subset of AXIS:– 25 fields chosen for follow-up: 3.3 deg2

– 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~23-24mag

• 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 Medium Shallow

Full sample

Breakdown of identified sources

XMS-S Soft

XMS-H Hard

XMS-X XID

XMS-U Ultrahard

Broad-line AGN

75% (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)

Stars 8% (15/200)

2% (3/132)

8% (20/261)

0% (0/60)

Redshift distribution

Peak of QSO distribution(z~1.5) well sampled.

Obscured population outto z~1 in Hard sample

Soft

Hard

z

z

#

#

Luminosities and redshifts

Soft

QSO-2 @ z=2.2

QSOs

“Seyferts”

z

z

All galaxiesconsistent with hosting

AGN LX>1042 erg/s:obscured AGN

log

(LS

oft c

gs)

log

(LH

ard

cg

s)

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

NH

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 NH)• 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 line @6.5±0.2 keV EW=130±60 eV: ~3 – NELG (113): =1.53±0.02 Fe line @6.6±0.4 keV EW=130±100 eV:

<~2

Averaging X-ray spectraCorral et al., in preparation

AXIS+XMM-2dFBLAGN

AXIS+XMM-2dFNELGs

• Procedure still being tested• Selecting X-ray spectra with >80cts• Unfolding with best fit Galactic+Intrinsic absorption power law• De-absorbing (correcting for Galactic NH)• 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 line @6.5±0.2 keV EW=130±60 eV: ~3 – NELG (113): =1.53±0.02 Fe line @6.6±0.4 keV EW=130±100 eV:

<~2

AXIS+XMM-2dFBLAGN

AXIS+XMM-2dFNELGs

Averaging X-ray spectraCorral et al., in preparation

Tips for statistical identification

~90% Obscured AGN (most Xabs)

90% unobscured AGN

Stars

HR2

log

(FH

ard

/Fop

t)

Full sample

X-ray to optical ratio:

a marker for obscuration?

Soft•5% of sources with FX/Fopt>10•≥40% of FX/Fopt>10 obscured AGN

FX/Fopt >10

Hard

log

(FH

ard

/Fop

t)

•15% of sources with FX/Fopt>10•~70% of FX/Fopt>10 obscured AGN

log

(FS

oft/F

op

t)

FX(10-

14cgs)

FX(10-14cgs)

Optical colours

QSOsS+Irr

E+S0

10% of QSOsare red

QSOsS+Irr

E+S0

HardSoft

r-i

g-r g-r

#

Optical versus X-ray “colours”: Hard

Hard Softer

Harder sources are >90% obscured AGNSofter sources: Optically blue: unabsorbed AGN Optically red: mix of abs & unabs AGN

HR2

g-r

Red

der

• 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 FX/Fopt>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. 2006 (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. 2007 (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