The Links Between AGN and Galaxy Formation Omar Almaini University of Nottingham

The Links Between AGN and Galaxy Formation Galaxy formation models …and their problems The AGN/galaxy connection Feedback and AGN winds Observing black hole/bulge growth Summary & future prospects

CDM cosmological model in excellent agreement with wide range of observations: e.g. CMB, galaxy clustering, type 1a SN, element abundances, Cepheid distance scale, stellar ages, baryon fraction in clusters…

Merger Tree for the Growth of a Dark-matter Halo

Semi-analytic Galaxy Formation Models + Messy physics (gas cooling, star-formation, dust, SN feedback etc…) N-body merger trees =

Hierarchical Galaxy Formation

Producing the local K-band luminosity function -SN feedback is essential! Benson (2003)

>5x1049 erg per solar mass required Problem can be solved with extreme super-winds >5x1049 erg per solar mass required Benson (2003)

Local galaxies are strongly bimodal Kauffmann et al. 2003; Balogh et al. 2004

Can’t make enough red galaxies at z>1 Data Model e.g. Daddi et al. 2002; Roche, Almaini et al. (2002), Roche, Dunlop & Almaini (2003); Somerville et al. (2003)

The diversity of ERO galaxies 30-40% old, passive systems 30-40% dusty starburst Typical redshifts 1.0<z<1.5 Strongly clustered High space density Many old, massive systems already in place at z~1-1.5

‘EROs’ at higher redshift Recent discovery of many old, passive systems at z>1.5 Using J-K>2 colour selection find population of very red galaxies at z>2 Cimatti et al. 2004 Glazebrook et al. 2004 Van Dokkum et al. 2003

Summary of galaxy formation problems Classic Problems Predicts too many dwarf gals Predicts “cuspy” cores Why are there no galaxies with  > 300 km/s? Newer Problems Fail to produce EROs Fails to predict SCUBA sources Bimodal local galaxy pop. Need a mechanism for switching off star-formation in most massive galaxies

II. The AGN/galaxy connection

All massive galaxies contain a SMBH

The black-hole/bulge mass relationship. MBH = 1.5x108 2004 M MBH = 0.2 % Mbulge Gebhardt et al. (2000), Ferrarese & Merritt (2000) c.f. Magorrian (1998)

Ebulge ~ Mbulge 2 ~ 10-6 Mbulge 2300 c2 Can the black hole influence its host galaxy? MBH = 2x10-3 Mbulge AGN radiative energy EAGN ~ 0.1 MBH c2 = 2 x 10-4 Mbulge c2 Binding energy of the bulge Ebulge ~ Mbulge 2 ~ 10-6 Mbulge 2300 c2 Less than 1% of the AGN energy could blow the galaxy apart

The X-ray background: Most accretion activity is absorbed Unobscured AGN

“AGN winds are ubiquitous” - Brad Peterson “My wind model explains everything” - Martin Elvis

APM-08279 – lensed BAL quasar at z=3.91 Fe XXV K ? v1~0.2 c v2~0.4c Chartas et al. (2002)

Massive X-ray outflow in PDS 456 XMM EPIC pn/MOS Reeves et al. (2003)

Massive X-ray outflow in PDS 456 XMM RGS-2 V~50,000 kms-1 NH = 5x1023 ~ 10 M yr-1 Momentum outflow: Mwind v ~ L Edd/c . Reeves et al. (2003)

Investigated supercritical accretion King & Pounds 2003 Investigated supercritical accretion M > M Edd . . ~ Assuming all excess matter ejected in a wind: Compton-thick, quasi-spherical outflow Momentum outflow: . Mwind v ~ f L Edd/c

Blandford 1999, Di Matteo et al. 2004… ) King 2003 (c.f. Silk & Rees 1998, Fabian 1999, Blandford 1999, Di Matteo et al. 2004… ) . Momentum outflow: Mwind v ~ L Edd/c Outflow drives wind bubble through host galaxy M(R)  2 R Mgas(R)  2 R Shell velocity v2  Ledd / 2 MBH  4

The black-hole/bulge mass relationship. MBH = 1.5x108 2004 M MBH = 0.2 % Mbulge Gebhardt et al. (2000), Ferrarese & Merritt (2000) c.f. Magorrian (1998)

Observations of AGN-driven super- winds now required!

A cartoon model of massive galaxy formation SCUBA phase quasar elliptical?

II. AGN in galaxy clusters

The Entropy Problem (SN not enough?)

The Cooling-Flow Problem XMM RGS (Virgo) Sakelliou et al. 2002

Chandra VLA

II. Observing joint black-hole/ galaxy formation

What is so special about submm sources? fn The James Clerk Maxwell Telescope (Hawaii) 1000 100 10 Wavelength / m

Results of submm surveys Highly luminous (ULIRG) systems SFR ~ 1000 M yr-1 Massive systems Evidence for outflowing winds Progenitors of massive elliptical galaxies?

Mass determinations for submm sources Genzel et al. (2003) Swinbank et al. (2004) Massive (CO) Massive (Ha)

Semi-analytic models have great difficulty producing submm sources… Baugh et al. (2005)

Most SCUBA sources DO NOT contain powerful quasars Almaini et al. 2003

William Herschel Telescope 4m 5 " William Herschel Telescope 4m Depth R~27 Seeing 0.7” 5 "

HST ACS Imaging – (Almaini et al. 2005) 5 " HST ACS Imaging – (Almaini et al. 2005)

1.945 Ms “True” color image ACIS-I exposure P.I.: W.N. Brandt 0.5-2.0 keV 2.0-4.0 keV 4.0-8.0 keV P.I.: W.N. Brandt

P.I.: W.N. Brandt Alexander et al. 2005 1.945 Ms ACIS-I exposure “True” color image 0.5-2.0 keV 2.0-4.0 keV 4.0-8.0 keV P.I.: W.N. Brandt 17/20 SCUBA galaxies X-ray detected Alexander et al. 2005

Joint spectral fitting Composite 2-20 keV spectra (12Ms) Joint spectral fitting 12Ms Chandra spectra!

Relatively low Lx/LFIR ratios

Evidence for growing black holes? 1.945 Ms ACIS-I exposure “True” color image 0.5-2.0 keV 2.0-4.0 keV 4.0-8.0 keV P.I.: W.N. Brandt Modest X-ray luminosities Lx = 1043-1044 ergs-1 Suggest black holes <108M Alexander et al. 2005 Evidence for growing black holes?

Eddington limited growth Fuel supply Eddington limited growth Archibald et al. (2002)

Where do we go from here? Need detailed prescription for AGN feedback in semi-analytic models. Can we detect merging black holes with LISA (Madau 2004)? How prevalent are AGN-driven winds? How massive were first black holes? What influence did they have on the IGM at z>10?

Conclusions Overwhelming evidence for CDM  hierarchical structure formation Problems with semi-analytical galaxy formation models - mechanism required to terminate SF in massive gals - plus other problems… AGN feedback is a likely solution - may be related to the origin of the M/ relation - could also explain high-mass cut-off & cluster heating problem