1. AEGIS-X: Results from the Chandra survey of the Extended Groth Strip
Elise Laird
A Georgakakis (NOA), K Nandra (PI: Imperial), J Aird (Imperial), D Croton (Berkeley), K Bundy (U Toronto), A Coil (Steward), C Pierce (UCSC), and the AEGIS team

2. All Wavelength Extra-Galactic International Survey
Deep multiwavelength data
Wide area (~ deg2)
Keck/DEIMOS DEEP2 spectroscopy: >10,000 redshifts with R<24.1, mainly 0.6<z<1.4
GALEX
Chandra
HST/ACS
Palomar
aegis.ucolick.org; Davis et al. (2007)
The X-ray Universe 2008, Granada

3. AEGIS-X survey 1.6 Ms over 0.67 deg2 (8 ACIS-I pointings)
Flux limits (1% complete);
SB (0.5-2 keV) 5.3 x cgs
HB (2-10 keV) 3.8 x10-16 cgs
1325 sources, selected between 0.5 and 7 keV
<1.5% spurious sources
0.79” astrometric accuracy
Laird et al. submitted to ApJS
The X-ray Universe 2008, Granada

4. AEGIS-X survey 1.6 Ms over 0.67 deg2 (8 ACIS-I pointings)
Flux limits (1% complete);
SB (0.5-2 keV) 5.3 x cgs
HB (2-10 keV) 3.8 x10-16 cgs
1325 sources, selected between 0.5 and 7 keV
<1.5% spurious sources
0.79” astrometric accuracy
AO9: additional 1.8 Ms over 0.2 deg2
Laird et al. submitted to ApJS
Reduced data, data products, catalogues publicly available at
The X-ray Universe 2008, Granada

5. AEGIS-X survey
---- L* at z=1
Using Maximum Likelihood technique to find secure counterparts:
optical: 76%, complete to RAB=24.1, 6% spurious matches
IRAC 3.6m: 94% (of sources with coverage), complete to mAB=23.8, 1% spurious matches
Currently ~35% spectroscopic completeness (with DEEP3  60%)
800ks data
Spectroscopy:
Keck/DEEP2 (Davis et al. 2003)
MMT (Coil et al. 2008)
The X-ray Universe 2008, Granada

6. AGN formation models “QSO mode”
Merger (QSO-mode) models (e.g. Hopkins et al. 2005):
• gas rich major merger
• gas inflows trigger BH accretion & starbursts
• dust/gas clouds obscure AGN
• AGN feedback sweeps away gas, quenching SF and BH accretion
“Radio mode”
Weak AGN feedback models in dense regions (e.g. Croton et al. 2006; Bower et al. 2006):
• cooling flows in groups or clusters
  large cold-gas reservoirs at galaxy centre
• weak AGN activity invoked to suppress cooling flows by either heating of mechanically sweeping away the gas
Hydra-A cluster, McNamara et al. 2000
Kazantzidis et al. 2005
The X-ray Universe 2008, Granada

7. Colour-magnitude relation
DEEP2 survey, 0.4<z<1.4; Willmer et al. 2006
Colour bimodality:
Blue cloud: star-forming
Red sequence: evolved stellar pop
Galaxy stellar mass builds via mergers in blue cloud
Rapid quenching RS
Are AGN responsible for quenching?
Or for maintaining galaxies on RS?
Dry mergers?
Quenching
Merger-driven star formation
e.g. Strateva et al 2001; Bell et al 2004; Faber et al 2007
The X-ray Universe 2008, Granada

8. Colour-magnitude relation for AGN
z= ; Nandra et al. 2007
The X-ray Universe 2008, Granada

9. Colour-magnitude relation for AGN
Are AGN responsible for the quenching?
Obscured X-ray sources in RED cloud: old stellar populations
X-ray surveys select AGN after the quenching of the star-formation
Are there obscured AGN (in star forming galaxies) below X-ray detection threshold?
Are obscured AGN found in post starburst galaxies? z= z=
Coil et al. 2008
The X-ray Universe 2008, Granada

10. X-ray stacking results: 24m bright sample
 Stack X-ray emission of galaxies at different regions of CMD and in post starburst galaxies
Georgakakis et al. 2008
Hard signal around valley and in red sequence, C>–0.15
Obscured AGN associated with transition galaxies
<Lx> = 1041 erg s-1
Stacked signal of 26 post starbursts: HR > <LX>~1041 ergs/s
The X-ray Universe 2008, Granada

11. AGN host galaxy morphologies
0.2<z<1.4
LX>1042 erg s-2
65% E/S0/Sa
Massive, bulge dominated, red, evolved hosts
Pierce et al. 2007
Gini coefficient: clumpiness; M20: central concentration
Abraham et al. 2003; Lotz et al. 2004
The X-ray Universe 2008, Granada

12. AGN stellar mass function
Hasinger et al. 2005
No Evidence for AGN hosts
“downsizing” in mass
Bundy et al. 2008
Accretion rate evolution?
Also Babic et al for z<1 in CFD-S
The X-ray Universe 2008, Granada

13. AGN: Massive galaxies tracing large scale structure
A. Coil
AGN: Massive galaxies tracing large scale structure
Also ECDF-S: Silverman et al. 2008; XBootes Murray et al. 2005; Hickox et al. 2008
The X-ray Universe 2008, Granada

14. AGN/Galaxy cross-correlation function
Split into 2 redshift bins: z= and z=
X-ray AGN cluster like red galaxies, at z~0.5 and z~0.9
Relative bias of X-ray AGN to galaxies:
z= red gals: 1.1 (0.1)
blue gals: 1.7 (0.1)
z= red gals: 1.1 (0.1)
blue gals: 1.4 (0.1)
Coil et al. 2006
Coil et al. 2008
The X-ray Universe 2008, Granada

15. AGN: relationship to groups
Gerke et al. (2006) optical spectroscopic groups
42% of X-ray AGN in groups
Excess compared to general population (~99%)
Tentative excess relative to matched galaxy population (~91%)
Tentative evidence that field AGN more luminous than group AGN (~98%)
X-ray
Randomised optical
Randomised optical
X-ray
Also Miyaji et al. 2007; Silverman et al. 2008
0.7< z< 1.4; Georgakakis et al. 2008
The X-ray Universe 2008, Granada

16. Conclusions Most black hole growth at z<1 not in “QSO mode”
Typical AGN at z~1 are in massive, red host galaxies
Star formation has terminated or is terminating
Many obscured AGN on red sequence
Bulge dominated, mergers not main trigger
Stellar Mass Function
Flat, non-evolving, no downsizing in mass
Large scale structure environment
Dense environments (cluster like hosts)
Around ~40% in groups
Most black hole growth at z<1 not in “QSO mode”
The X-ray Universe 2008, Granada

17. AEGIS-X advertisement
All reduced data and data products for AEGIS-X released 1 May 2008.
Processed other Chandra deep fields in same way and reduced data, data products & source catalogues also released
Chandra Deep Field North (2Ms)
Chandra Deep Field South (2Ms)
Extended Chandra Deep Field South (4 x 250 ks)
Also large area, shallow ELAIS-N1 and XBootes surveys
The X-ray Universe 2008, Granada