Active Galactic Nucleian Historical Review

Meg UrryYale University

•• Black hole Black hole •• Accretion disk Accretion disk •• Hot corona Hot corona •• BroadBroad--line region line region •• NarrowNarrow--line region line region •• Obscuring gas/dust Obscuring gas/dust •• (Relativistic jets)(Relativistic jets)

AGN ElementsAGN Elements

M

M•

EnvironmentInteractions Star-formation Stripping Obscuration

θ

z

Relativistic beamingradio, optical, X-ray, γ-ray

Obscuration

Evolution

B

(Partial) Review of AGN

• Relativistic beaming and jets

• AGN demographics at “quasar epoch” (z ∼ 2)

• Feedback and co-evolution of BH & galaxies

>

Relativistic Beaming

• Rapid variability• Superluminal motion• X-ray jets• Population demographics

Rapid Variability (gamma rays)

5 days

x10

Mattox et al.

NGC 6251 radio structure

Superluminal Motion

50 light years

3C279 Wehrle et al. 2001

Uchiyama et al. 2006, Jester et al. 2006

3C 273 Jet

1″

Population statistics confirm relativistic beaming

• Radio galaxies are parent population of blazars Schwartz, Orr & Browne

• Luminosity functions match (R,X,O) Urry, Padovani

• Radio counts match Wall & Jackson

• Possible evolutionary sequences OVV→BL Lac, FR2 →FR1 Cavaliere, Maraschi

• Blazar “family” in accretion/jet power Fossati, Ghisellini

Remaining Questions • Extraction of energy from BH

– Jet power kinetic luminosity function

– Magnetic field configuration– Role of disk

• Physics of jets– Matter content (Protons?)– Power– Particle acceleration

• Radio-loud v. radio-quiet – Nature or nurture?

Obscuration

• Hard X-ray background

• Spectropolarimetry (local AGN)

• Demographics in deep multiwavelength surveys

X-ray “Background” Spectrum

Courtesy Brusa, Comastri, Gilli, Hasinger

unabsorbed AGN spectrum

Increasing NH

Extended Chandra Deep Field-South

MUSYC, GOODS surveys:UBVRIz JHK, NB & MB imagingHST, Spitzer, Chandra, VLT, Gemini, Subaru,

Magellan, KPNO, CTIO, VLA, AT, …

Brandt et al. 2006, Virani et al. 2006Dickinson, Giavalisco, Koekemoer, Rix & GEMS team,

Gawiser, van Dokkum, Kriek, Taylor, CMU, …

HST ACS color image (0.3% of GOODS)

HST+Spitzer color image (0.3% of GOODS)

AGN in Deep Surveys• Obscured AGN dominate population Treister et al. 2004, 2005,

2006a,b,c– optical counts, N(z) well fit by 3:1 ratio, 50% AGN not in

CDFs– fits X-ray background– fits IR counts; LAGN,IR ∼10x LGal,IR; low AGN % of IR

extragalactic light– Integral & BAT surveys constrain Compton-thick AGN, BH

accretion history– Obscured/unobscured ratio decreases with luminosity Barger et

al. 2005, Hasinger et al. 2005– meta-analysis shows obs/unobs ratio increases with z

• Hard X-ray background dominated by obscured AGN Giacconi et al. 1979, Setti & Woltjer 1989, Madau et al. 1994, Comastri et al. 1995, Gilli et al. 2001, Worsley et al. 2005

• FIR Searches find candidates Polletta et al., Alonso-Herrero et al.

CreateCreate ensemble of AGNAGN, with continuous range of obscuration,

correct SEDs for Unification (type i sed + obsc),known luminosity distribution,

known cosmic evolutionGenerate expected survey Generate expected survey

content content at X-ray, Optical, Infrared, or any wavelengths,

as function of Flux and RedshiftCompare to dataCompare to data

GOODS, MUSYC,GOODS, MUSYC,SEXSI, SWIRE, CLASXS, H2XMM, AMSS, Groth,

COSMOS, Lockman, CHAMP, …

Treister et al. 2004

Treister et al. 2004

redshifts of Chandra deep X-ray sources

GOODS-N

Barger et al. 2002,3, Hasinger et al. 2002, Szokoly et al. 2004

redshifts of Chandra deep X-ray sources

GOODS-N

Barger et al. 2002,3, Hasinger et al. 2002, Szokoly et al. 2004

Treister et al. 2005, Gilli et al. 2006

X-ray background synthesis

X-ray background synthesis

Treister et al. 2005, Gilli et al. 2006

X-ray background synthesis

Treister et al. 2005, Gilli et al. 2006

AGN in Deep Surveys• Obscured AGN dominate population Treister et al. 2004, 2005,

2006a,b,c– optical counts, N(z) well fit by 3:1 ratio, 50% AGN not in

CDFs– fits X-ray background– fits IR counts; LAGN,IR ∼10x LGal,IR; low AGN % of IR

extragalactic light– Integral & BAT surveys constrain Compton-thick AGN, BH

accretion history– Obscured/unobscured ratio decreases with luminosity Barger et

al. 2005, Hasinger et al. 2005–– metameta--analysis shows analysis shows obs/unobsobs/unobs ratio increases with zratio increases with z

• Hard X-ray background dominated by obscured AGN Giacconi et al. 1979, Setti & Woltjer 1989, Madau et al. 1994, Comastri et al. 1995, Gilli et al. 2001, Worsley et al. 2005

• FIR Searches find candidates Polletta et al., Alonso-Herrero et al.

7 surveys

2341 AGN

1229 with z

Area as function of X-ray flux & optical mag

Treister & Urry 2006

Treister & Urry 2006

Treister & Urry 2006

AGN in Deep Surveys• Obscured AGN dominate population Treister et al. 2004, 2005,

2006a,b,c

• Hard X-ray background dominated by moderate-luminosity obscured AGN at 0.5<z<1.5 Giacconi et al. 1979, Setti & Woltjer 1989, Madau et al. 1994, Comastri et al. 1995, Gilli et al. 2001, Worsley et al. 2005

– Only 60% (50%) XRBG resolved at 6-8keV (8 keV)• Consistent with missing population of highly obscured AGN

– Luminosity-dependent density evolution Ueda et al. 2003, Barger et al. 2005

• FIR Searches find candidates Polletta et al., Alonso-Herrero et al.

Luminosity-dependent density evolution

Hasinger et al. 2005

>1046 ergs/s

1045-6 ergs/s

1044-5 ergs/s1043-4 ergs/s1042-3 ergs/s

AGN in Deep Surveys• Obscured AGN dominate population Treister et al. 2004, 2005,

2006a,b,c

• Hard X-ray background dominated by obscured AGN Giacconi et al. 1979, Setti & Woltjer 1989, Madau et al. 1994, Comastri et al. 1995, Gilli et al. 2001, Worsley et al. 2005

• FIR Searches find candidates Polletta et al., Alonso-Herrero et al.

–– Up to x2 missing from XUp to x2 missing from X--ray surveysray surveys–– Works best at bright IR fluxes (>1 Works best at bright IR fluxes (>1 mJymJy))–– IR catalog dominated by star formationIR catalog dominated by star formation–– IR spectral cuts miss some bona fide AGNIR spectral cuts miss some bona fide AGN

Remaining Questions • Spectrum of AGN above 10 keV

– Hard X-ray large-area survey

• Evolution of AGN– With luminosity

– At different wavelengths

•• MMBHBH -- σσ relation relation • All (nearby) galaxies host black holes• Common evolution• AGN host galaxies appear normal

– Fundamental plane, evolution O’Dowd et al. 2005, Woo et al. 2005

• AGN feedback on galaxies– Central cluster galaxies (e.g., Perseus A)– Goldilocks for galaxies ⎯ not too big, not too small?

The formation and evolution of galaxiesis closely tied to

the growth of black holes

MBH related to galaxy bulge

in normal and active galaxies

Kormendy & Gebhardt 2001

• MBH - σ relation •• All (nearby) galaxies host black holesAll (nearby) galaxies host black holes• Common evolution• AGN host galaxies appear normal

– Fundamental plane, evolution O’Dowd et al. 2005, Woo et al. 2005

• AGN feedback on galaxies– Central cluster galaxies (e.g., Perseus A)– Goldilocks for galaxies ⎯ not too big, not too small?

The formation and evolution of galaxiesis closely tied to

the growth of black holes

• MBH - σ relation • All (nearby) galaxies host black holes•• Common evolutionCommon evolution• AGN host galaxies appear normal

– Fundamental plane, evolution O’Dowd et al. 2005, Woo et al. 2005

• AGN feedback on galaxies– Central cluster galaxies (e.g., Perseus A)– Goldilocks for galaxies ⎯ not too big, not too small?

The formation and evolution of galaxiesis closely tied to

the growth of black holes

Rate of cosmic BH/star formation(measured) BH growth ratestar formation rate (GOODS)

ρ BH

(Mo

yr−1

Mpc

−3)

• MBH - σ relation • All (nearby) galaxies host black holes• Common evolution•• AGN host galaxies appear normalAGN host galaxies appear normal

– Fundamental plane, evolution O’Dowd et al. 2005, Woo et al. 2005

• AGN feedback on galaxies– Central cluster galaxies (e.g., Perseus A)– Goldilocks for galaxies ⎯ not too big, not too small?

The formation and evolution of galaxiesis closely tied to

the growth of black holes

• MBH - σ relation • All (nearby) galaxies host black holes• Common evolution• AGN host galaxies appear normal

– Fundamental plane, evolution O’Dowd et al. 2005, Woo et al. 2005

•• AGN feedback on galaxiesAGN feedback on galaxies– Central cluster galaxies (e.g., Perseus A)– Goldilocks for galaxies ⎯ not too big, not too small?

The formation and evolution of galaxiesis closely tied to

the growth of black holes

X-ray image of Perseus cluster of galaxies

NASA/CXC/IoA/Fabian et al. 2003

Simmons et al., in prep.

Optical imaging of host galaxies

(Lots of) Questions remaining

• Feedback, co-evolution of galaxies and BH– Phasing of BH growth and star formation– Relative time scales– Energy deposition from AGN– Evolution of mass function of black holes

• Galaxy observables– Host galaxy mass– Star formation rates, stellar populations– Environmental effects

What we will learn about AGN in the next 30 years (i)

• Processes near BH– Formation, acceleration, collimation of jets– Evolution along jet (B, N, Γ)– Cosmic ray production, particle acceleration

• BH Energetics– Magnetic fields, energization of corona– Matter content of jets – Accretion disk structure and physics

What we will learn about AGN in the next 30 years (ii)

Deborah Dultzin-Hacyan

has worked on nearly every topic I mentioned (and more besides)!

In the last 30 years,

Backup Slides

Radio loud v. Radio quiet

Is radio loudness bimodal?Could relativistic jets form near all black holes?

Bimodality: PG quasars

R

Quasars

AGNN

umbe

r

Kellerman et al. VLA OBSERVATIONS OF PG QUASARS

FIRST quasars

White et al. 2001

Blazars: the spectral sequence

FSRQ

BL Lacs

Fossati et al. 1998; Donato et al. 2001

RED

BLUE

Blazars: emission models lman & Rees 1994; Dermer(Maraschi, Ghisellini & Celotti 1992; Sikora, Bege & Schlickeiser 1993 ...)

Resolved X-ray jet

Blazar emission region

Accretion region

Internal shock modelSpada et al. 2001

B = 0.6 - 0.5 δ = 17.8 - 12.3 γb = 550 - 600 Ballo et al. 2002

3C279EC + SSC

Ghisellini Celotti & Costamante 2002

Physical Parameters along the Spectral Sequence

Jet Power

where

Blazars: Power and Matter Content

Maraschi & Tavecchio 2004

Pe < Ljet Protons Celotti & Ghisellini 2002

(but see Wardle 1998, Hirotani et al. 2000for pc-scale jets)

Cygnus A radio galaxy (FR 2)

Carilli et al.

M87 Radio Galaxy (FR I)

Owen et al.

M87 (nearby AGN)

dec

0 RA 24

van Dokkum, Gawiser, Urry, Lira…

MUSYC: MUSYC: 1 deg2, UBVRIzJHK+NB, Spitzer, HST, Chandra, XMM, Galex, VLT, Magellan, Gemini, …

Black hole demographics

• Most AGN are obscured (locally)• X-ray “background” from obscured AGN,

– 1043-1044 erg/s– z<1

• Peak BH accretion (& star formation) z~2• BH accretion:

– How many? (relation to local MBH)– When? (relation to galaxies)

~

AGN in Deep Surveys• Obscured AGN dominate population Treister et al. 2004, 2005, 2006a,b,c

– optical counts, N(z) well fit by 3:1 ratio, 50% AGN not in CDFs– fits X-ray background– fits IR counts; LAGN,IR ∼10x LGal,IR; low AGN % of IR extragalactic light– Integral survey constraints on Compton-thick AGN, BH accretion history– Obscured/unobscured ratio decreases with luminosity Barger et al. 2005– meta-analysis shows obs/unobs ratio increases with z

• Hard X-ray background dominated by obscured AGN Giacconi et al. 1979, Setti & Woltjer 1989, Madau et al. 1994, Comastri et al. 1995, Gilli et al. 2001, Worsley et al. 2005

– Only 60% 6-8keV XRBG resolved– Only 50% at 8 keV– Consistent with missing population of highly obscured AGN

• FIR Searches find candidates but – Dominated by star formation– Spectral cuts miss some bona fide AGN

EzequielEzequiel TreisterTreister, CMU, Jeffrey van Duyne, Brooke Simmons, Eleni Chatzichristou (Yale U.), David Alexander, Franz Bauer, Niel Brandt (Penn State U.), Anton Koekemoer, Leonidas Moustakas (STScI), Jacqueline Bergeron (IAP), Ranga-Ram Chary (SSC), Christopher Conselice (Caltech), Stefano Cristiani (Padova), Norman Grogin (JHU) 2004, ApJ, 616, 123 Hard X-ray LF & evolution for Type 1 AGN Ueda et al. 2004

• Grid of AGN spectra (LX,NH) with – SDSS quasar spectrum (normalized to X-ray)– dust/gas absorption (optical/UV/soft X-ray) – infrared dust emission Nenkova et al. 2002, Elitzur et al. 2003– L* host galaxy

• Geometry with obscured AGN = 3 x unobscured, at all z• Calculate expected redshift distribution – compare to measured

redshifts of GOODS AGN• Calculate expected optical magnitudes of X-ray sources in GOODS

fields – compare to GOODS HST data • Calculate expected N(S) for infrared sources – compare to GOODS

Spitzer data

Dust emission models from Nenkova et al. 2002, Elitzur et al. 2003Simplest dust distribution that satisfies

NH = 1020 – 1024 cm-2

3:1 ratio (divide at 1022 cm-2)Random angles NH distribution

“EXO” Extreme X-ray-to-Optical AGN

B V R BVR

Z J K

KAB = 21.4 X-ray

ECDFS ID: 29

R-K = 7.88Blue Green Red Composite optical

Redder Near-IR Reddest Near-IR

•very high redshift AGN with z > 6, or•very obscured AGN w old/dusty host galaxies at z~2

EXOs in MUSYC ECDFS

Determining the nature of EXOs

• No EXO has measured spectroscopic z• SEDs consistent w z∼2 or z>6• Near-infrared spectroscopy needed• Current Gemini time, VLT proposal

LBol=1043 LBol=1045

Woo et al. 2002a

Relation of MBH to AGN activity (?)

Evolution of M/L ratio in host galaxies — same as normal galaxies

Woo et al. 2005Woo et al. 2005

kpc-scale jets: speed and power

Chandra detections allows us to constrainthe physical parameters of jets at kpc scale

In the case of powerful quasars models give:

Γ~3-10 P~1046 -1048 erg/sSupported by recent numerical simulations (Scheck et al. 2002), but see Wardle & Aaron 1997

Fast spine? (Chiaberge et al. 2000; Celotti et al. 2001)

Jets and accretionExtraction of power from the rotating BH (Blandford & Znajek 1976) or from the disk (Blandford & Payne 1982)

In both cases the extractable power depends on the valueof the magnetic field close to the BH

But how the intensity and structure of the field are related to the accretion rate is a complex issue (e.g. Ghosh and Abramowicz 97, Livio et al. 99, Krolik 99, Meier 99)

A Unified Scenario

Blazars (from BL Lacs to FSRQs) and strong radio sources (from FRI to FRII) have similar engines.

The range in observed properties is determined by the accretion rate in Eddington units.

CRITICAL for high luminosity objectsSUBCRITICAL for low luminosity objects

The scenario explains

• Presence/absence of emission lines in high/low powerobjects (efficient/inefficient accretion disk)

• Spectral sequence : larger cooling due to BLR photons produces redder SEDs in high power blazars

(Bottcher and Dermer, 2002)

• Lower magnetic field and lower pressure in low power jets

• Cosmological evolution due to decrease of accretion rate with cosmic time (Cavaliere and D'Elia 2002)

• The scenario is testable by measuring the masses of central BHs in AGN

Barth et al. 2002, Falomo et al. 2002 Mkn 501: 109M

Summary 1: jets at subpc to kpc scaleHigh power blazars have red SEDs due to low internal particle

energies; gamma-rays (GeV) are produced via the EC process.

Low power blazars have blue SEDs due to high internal particleenergies; gamma-rays (up to TeV) are produced via SSC.

The jet radiative efficiency is negligible close to the BH,it is 1-10% in the blazar emission region (100-1000 Rs) anddecreases further out (agreement with internal shock model).

X-ray knots resolved by CHANDRA in distant powerful jets aredue to IC on CMB. These jets are still relativistic on very large scales. Magnetic field compatible with free expansion.Jet pressure at X-ray knots comparable with external pressure.

Summary ctd.: the jet disk connectionAt high luminosity Ljet ~ Ldisk and both efficiencies are ~10%.

Then Pjet ~ Pacc (not easy to achieve theoretically even formaximally rotating BH).

At low luminosity Ljet is larger then Ldisk. This can onlybe understood if the radiative efficiency of the disk is low.

The power scale, the spectral sequence, the emission lineproperties of blazars can be understood within a physicallyunified scenario where the main parameter is the accretion ratein Eddington units.

Measurements of the masses of central black holes in AGN cantest the proposed scenario.

Van Duyne et al. 2006

Objects with hard Objects with hard (absorbed) XX--ray ray spectra:spectra:

(weak) AGN or galaxy in optical

luminous thermal infrared emission

AGN SEDs in GOODS

Van Duyne et al. 2006