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Page 1: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Suzy Collin-ZahnSuzy Collin-Zahn

LUTH, Observatoire de Paris MeudonLUTH, Observatoire de Paris Meudon

AGN, MASSIVE BLACK HOLES, ACCRETIONAGN, MASSIVE BLACK HOLES, ACCRETION

ARE AGN FACTORIES OF HIGH ENERGY ARE AGN FACTORIES OF HIGH ENERGY PARTICLES AND PHOTONS?PARTICLES AND PHOTONS?

OROR

Page 2: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

THE CONTEXTTHE CONTEXT

DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDSAND JETS / WINDS

STRONG AND WEAK ACCRETORSSTRONG AND WEAK ACCRETORS

CONCLUSIONCONCLUSION

Page 3: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

THE CONTEXTTHE CONTEXT

DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDSAND JETS / WINDS

STRONG AND WEAK ACCRETORSSTRONG AND WEAK ACCRETORS

CONCLUSIONCONCLUSION

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Blois 2008

1.1. Active Galactic Nuclei: from quasars (L=10Active Galactic Nuclei: from quasars (L=1046-4846-48 erg/s) to erg/s) to Seyfert galaxies (L=10Seyfert galaxies (L=1043-4643-46 erg/s), and Low Luminosity erg/s), and Low Luminosity AGN (L=10AGN (L=1040-4340-43 erg/s) erg/s)

RECALL OF SOME WELL-KNOWN FACTSRECALL OF SOME WELL-KNOWN FACTS

2. Power derived from accretion onto a supermassive black 2. Power derived from accretion onto a supermassive black holehole

3. BH present in ALL NUCLEI of galaxy, M(BH) from L=103. BH present in ALL NUCLEI of galaxy, M(BH) from L=1010 10 to 10to 1055 M M , M(BH) ~ M(Bulge)/1000, M(BH) ~ M(Bulge)/1000

4. « Unified Scheme »4. « Unified Scheme »

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Black hole

Absorbing torus

Narrow line region

Broad line region

Accretion disk

(RL or RQ)

(FRI) (FRII)

Wind

radio galaxies

LINERs

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Blois 2008

MIL

LIO

NS

OF

LIG

HT

-YE

AR

S

Faranoff-Riley, 1974Faranoff-Riley, 1974

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Blois 2008

SOME FIDUCIAL VALUESSOME FIDUCIAL VALUES

Eddington luminosityEddington luminosity

gravitational radius:gravitational radius: =1.5 10=1.5 101313 MM88 cm ~10cm ~10-5 -5 pcpc

bolometric luminositybolometric luminosity

where is the accretion ratewhere is the accretion rate

rmaximum radiation efficiency of mass-energy conversionrmaximum radiation efficiency of mass-energy conversion0.057 for a Schwarzschild BH, R(ISCO)=6Rg0.057 for a Schwarzschild BH, R(ISCO)=6Rg

0.3 for a maximally rotating Kerr BH, R(ISCO)~1Rg0.3 for a maximally rotating Kerr BH, R(ISCO)~1Rg

M•

Lbol = ε M•

c 2

Lbol = ε M•

c 2

QuickTime™ et un décompresseurGIF sont requis pour visualiser

cette image.

QuickTime™ et un décompresseurGIF sont requis pour visualiser

cette image.

= 1.3 10= 1.3 104646 MM88 erg/serg/s

M•

= ε

0.1 L46 0.6 Mo/yr

M•

= ε

0.1 L46 0.6 Mo/yr

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Blois 2008

HOW TO FUEL BLACK HOLES?HOW TO FUEL BLACK HOLES?

The angular momentum (The angular momentum (GMR)GMR)1/21/2 must be transported outward! must be transported outward!

Major and minor mergers (quasars)Major and minor mergers (quasars)Tidal interactions between galaxies (luminous Seyfert)Tidal interactions between galaxies (luminous Seyfert)

Bars, bars within bars, nonaxisymmetric potentials (weak Seyfert)Bars, bars within bars, nonaxisymmetric potentials (weak Seyfert)Dynamical friction of molecular clouds (LLAGN)…Dynamical friction of molecular clouds (LLAGN)…

1. At large distances (≥ 100pc)1. At large distances (≥ 100pc)

2. At small distances (<1pc)2. At small distances (<1pc)

« ACCRETION DISKS »« ACCRETION DISKS » local turbulent viscosity (MRI, possibly)local turbulent viscosity (MRI, possibly)

3. At intermediate distances3. At intermediate distances

Still unknown! Gravitational instability?Still unknown! Gravitational instability?

or global transport of AM via an organized magnetic field?or global transport of AM via an organized magnetic field?

Page 9: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

THE CONTEXTTHE CONTEXT

DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDSAND JETS / WINDS

STRONG AND WEAK ACCRETORSSTRONG AND WEAK ACCRETORS

CONSLUSIONCONSLUSION

Page 10: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

In local UniverseIn local Universe

Luminous AGN : ~ 1% of all galaxiesLuminous AGN : ~ 1% of all galaxies

Low Luminosity AGN : ~ 40% of all galaxiesLow Luminosity AGN : ~ 40% of all galaxies

The remainder 60%: dormant BHThe remainder 60%: dormant BH

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Blois 2008

m •

= M•

/ Mcrit

, with M•

crit = LEdd /c 2

m •

< .001: weak accretors

m •

> .01: strong accretors

m •

= M•

/ Mcrit

, with M•

crit = LEdd /c 2

m •

< .001: weak accretors

m •

> .01: strong accretors

ACCRETION DISKS:ACCRETION DISKS:

INFLUENCE OF THE ACCRETION RATEINFLUENCE OF THE ACCRETION RATE

Page 12: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Spectral distribution of Seyfert and RQQ,Spectral distribution of Seyfert and RQQ,no radio or gamma radiation, everything is thermal!no radio or gamma radiation, everything is thermal!

synchrotronsynchrotron

dustdust

cold accretion diskthermal Compton

cold accretion diskthermal Compton

hot corona

thermal Compton

hot corona

thermal Comptoninverse

Compton

inverse

Compton

thermal emission

accretion

thermal emission

accretion

A. STRONG ACCRETORSA. STRONG ACCRETORS

Observations by Sanders et al. 1989

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Blois 2008

Thin disks, H/R <<0.1, optically thick, emit the « Big Blue Bump »Thin disks, H/R <<0.1, optically thick, emit the « Big Blue Bump »SeyfertSeyfert

Quasars, Narrow Line Seyfert 1 (NLS1s)Quasars, Narrow Line Seyfert 1 (NLS1s)

« slim » disks, H/R ~0.1, optically thick, radiation pressure, « slim » disks, H/R ~0.1, optically thick, radiation pressure, emit the « Big Blue Bump »emit the « Big Blue Bump »

0.1< m •

< 3

0.1< m •

< 3

3 < m •

<10

3 < m •

<10

I.I.

II.II.

« Thick » disks, H/R~1, optically thick, radiation pressure,« Thick » disks, H/R~1, optically thick, radiation pressure,

emit soft X-rays, emit soft X-rays, photons cannot escape, thusphotons cannot escape, thus

Some low mass NLS1s (10Some low mass NLS1s (106-76-7Mo), in growing processMo), in growing process

10 < m •

10 < m •

III.III.

L /LEdd ~ 1 << m.

L /LEdd ~ 1 << m.

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Blois 2008

CONTROVERSY ABOUT THICK DISKSCONTROVERSY ABOUT THICK DISKS

Do these boulimic accretors exist? Do these boulimic accretors exist?

MHD simulations seems to show that if m >> 10 at large distance, MHD simulations seems to show that if m >> 10 at large distance,

strong outflows are expelled at smaller distance, strong outflows are expelled at smaller distance,

and theand the accretion rate on the BHaccretion rate on the BH remains limited remains limited

at the Eddington value.at the Eddington value.

.

Page 15: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

NO HARD X-RAYS ARE EXPECTED FROM THESE DISKS

proof of the presence of a hot medium emitting the hard X-rays proof of the presence of a hot medium emitting the hard X-rays whose emission is « reflected » by the diskwhose emission is « reflected » by the disk

Inte

nsity

Energy in keV

MCG _6_30_15

Iron K line

Relativistic profile of FeK Relativistic profile of FeK the disk extends down to ~10Rg, and the disk extends down to ~10Rg, and sometimes to ~1Rg sometimes to ~1Rg ISCO of a rapidly spinning BH ISCO of a rapidly spinning BH

BUT

Fabian et al. 2006

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Blois 2008

The reflection model: radiatively coupled disk + coronaThe reflection model: radiatively coupled disk + corona

Done, Gierlinski , 2004Done, Gierlinski , 2004

Same radiation coupling, but more realistic model : Same radiation coupling, but more realistic model : disk + « magnetic flares »disk + « magnetic flares »

Corona Corona Compton-Compton-

cooled cooled by UVby UV

photonsphotons

Disk heated byDisk heated by gravitationalgravitational

release release AND X-raysAND X-rays

Page 17: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Optically thin, geometrically thick, hot (relativistic) disks, Optically thin, geometrically thick, hot (relativistic) disks, emitting mainly radio and X-rays,emitting mainly radio and X-rays,

Gas falls into the BH before radiating, thus Gas falls into the BH before radiating, thus

L /LEdd << m •

L /LEdd << m •

LLAGN, radio galaxies FRI (M87..), Galactic CenterLLAGN, radio galaxies FRI (M87..), Galactic Center

B. WEAK ACCRETORS

m •

≤ 0.001

m •

≤ 0.001

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Blois 2008

Inflated codona, or…Inflated codona, or………suppression of the inner suppression of the inner regions of accretion diskregions of accretion disk

The « Big Blue Bump » does not existThe « Big Blue Bump » does not exist

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Blois 2008

CONTROVERSY ABOUT THESE DISKSCONTROVERSY ABOUT THESE DISKS

Which model for these anorexic accretors? Which model for these anorexic accretors?

ADAF, ADIOS, CDAF… RIAFADAF, ADIOS, CDAF… RIAF

Is there also a jet?Is there also a jet?

Page 20: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Yuan, Quataert, Narayan, 2003

Synchrotron and Inverse Compton by thermal electrons

Synchrotron and Inverse Compton by non-thermal electrons

(jet or ADAF?) bremsstrahlung

ADAF+JET FOR A « QUIESCENT » BH: ADAF+JET FOR A « QUIESCENT » BH: THE GALACTIC CENTERTHE GALACTIC CENTER

measured M~3 10measured M~3 10-6-6 M Mo o /yr/yr L (for L (for ~0.1) should be ~ 10 ~0.1) should be ~ 1041 41 erg/serg/s

quiescent

flaring

.BUT measured L~ 10BUT measured L~ 1036 36 erg/serg/s L/LL/LEdd Edd ~ 3 10~ 3 10-9-9,, ~ 10~ 10-6-6

Page 21: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

a Sgr A* Jet?

~ 1 pc

F. Baganoff et al. 2003

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ADAF+JET MODEL FOR A FRI GALAXYADAF+JET MODEL FOR A FRI GALAXY

L/LL/LEdd Edd ~ 3 10~ 3 10-4-4

ADAFJet

Wu, Yuan, Cao, 2008

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Blois 2008

CONCLUSION:CONCLUSION:

BOTH STRONG AND WEAK ACCRETORS ARE BOTH STRONG AND WEAK ACCRETORS ARE RADIATIVELY INEFFICIENTRADIATIVELY INEFFICIENT

DISKS MUST PRODUCE OUTFLOWS TO DISKS MUST PRODUCE OUTFLOWS TO EVACUATE THEIR ENERGYEVACUATE THEIR ENERGY

Page 24: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

THE CONTEXTTHE CONTEXT

DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDSAND JETS / WINDS

STRONG AND WEAK ACCRETORSSTRONG AND WEAK ACCRETORS

CONCLUSIONCONCLUSION

Page 25: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

AGN are divided in « Radio Loud » (RL) and « Radio Quiet » (RQ)AGN are divided in « Radio Loud » (RL) and « Radio Quiet » (RQ)

Sikora, Stawarz, Lasota, 2007

BLRG

LINERS

RQQ

RLQ

SEYFERTS

FRI

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Blois 2008

Mc Lure, Dunlop 2004

With a complete sample of quasars (SDSS)With a complete sample of quasars (SDSS)

Number of RLQ are less than 10% of RQQNumber of RLQ are less than 10% of RQQ

R = Lradio(5GHz) / Lopt

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Blois 2008

Log(L/Ledd)

LINERS

RQQSEYFERTS

RADIO LOUDNESS DEPENDS ON THE EDDINGTON FACTORRADIO LOUDNESS DEPENDS ON THE EDDINGTON FACTOR

BLRG

RLQ

FRI

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Blois 2008

LINERS, SEYFERTS

RQQ

RADIO LOUDNESS DEPENDS ON M(BH)RADIO LOUDNESS DEPENDS ON M(BH)

BLRG

RLQ

FRI

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Blois 2008

1. 1. LocallyLocally RL are exclusively in elliptical galaxies, RL are exclusively in elliptical galaxies,

RQ in spiral galaxies RQ in spiral galaxies

DIFFERENCES BETWEEN RL AND RQDIFFERENCES BETWEEN RL AND RQ objectsobjects

2. RLs are associated with non-thermal relativistic collimated 2. RLs are associated with non-thermal relativistic collimated jetsjets,,

RQs seem associated with thermal non-collimated RQs seem associated with thermal non-collimated windswinds

(detected by Broad Absorption Lines and X-ray absorbers)(detected by Broad Absorption Lines and X-ray absorbers)

3. Several more subtile properties, not understood 3. Several more subtile properties, not understood

(i.e. intense FeII lines only in RQs)(i.e. intense FeII lines only in RQs)

I. HIGH LUMINOSITY AGN

WHY?WHY?

Page 30: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

JETS VERSUS WINDSJETS VERSUS WINDS

Jets are launched at R ≤ 1000 Rg (VLBI)Jets are launched at R ≤ 1000 Rg (VLBI)

Winds are launched at R ≥ 10000RgWinds are launched at R ≥ 10000Rg

OBSERVATIONSOBSERVATIONS

Jets have relativistic bulk velocities and are made of relativistic Jets have relativistic bulk velocities and are made of relativistic particlesparticles

Winds have velocities from few hundreds km/s to c/10 and Winds have velocities from few hundreds km/s to c/10 and consist of warm (10consist of warm (105-6 5-6 K) thermal gasK) thermal gas

Page 31: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Magnetic field is indispensable to explain extended jet acceleration:Magnetic field is indispensable to explain extended jet acceleration:

1. Centrifugally driven flow1. Centrifugally driven flow

2. Extraction of the 2. Extraction of the rotational energyrotational energy of the BHof the BH: : field connects the BH to the diskfield connects the BH to the disk

(Blandford-Znajek, 1977) (Blandford-Znajek, 1977)

JET DRIVING MECHANISMJET DRIVING MECHANISM

Jets might be linked with the spin of the BHJets might be linked with the spin of the BH

Page 32: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

BLACK HOLE SPINBLACK HOLE SPIN

1. Even RQ AGN have spinning BH (FeK line)1. Even RQ AGN have spinning BH (FeK line)

2. Cosmological evolution of AGN requires large fraction of 2. Cosmological evolution of AGN requires large fraction of spinning BHs (mass-conversion efficiency must be > 0.06)spinning BHs (mass-conversion efficiency must be > 0.06)

Measured by dimensionless angular momentum Measured by dimensionless angular momentum a = J/Jmax = cJ/GMa = J/Jmax = cJ/GM22

4. It is expected that 4. It is expected that aa increases with accretion AND with merger increases with accretion AND with merger of two BHsof two BHs

3. Power of the jet must increase with 3. Power of the jet must increase with aa

5. BHs increase with galaxy bulges, and a fraction of elliptical 5. BHs increase with galaxy bulges, and a fraction of elliptical galaxies (large bulges) are due to the merger of spirals galaxies (large bulges) are due to the merger of spirals

Elliptical galaxies favor high spin, therefore jetsElliptical galaxies favor high spin, therefore jets

Page 33: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

But it does not explain all:But it does not explain all:Other mechanisms must be at workOther mechanisms must be at work

1.1. Environnement can play a role:Environnement can play a role:spiral galaxies contain cold gas, ellipticals contain and are surrounded by hot gas

2. Geometry of the inner disk can play a role: 2. Geometry of the inner disk can play a role: thick or thinthick or thin

3. Density profile of the circumnuclear regions can play a role: 3. Density profile of the circumnuclear regions can play a role: cusp or corecusp or core

etc… etc…etc… etc…

Page 34: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

DO THEY HAVE JETS? YES! DO THEY HAVE JETS? YES!

Falcke et al; 2000

A sample of Low Luminosity AGNA sample of Low Luminosity AGN

Compact jet structure with flat spectra observed in 40% of LLAGNCompact jet structure with flat spectra observed in 40% of LLAGN

(bulge)

large M(BH) small M(BH)

II. LOW LUMINOSITY AGN II. LOW LUMINOSITY AGN

but no detailed mechanism proposed so farbut no detailed mechanism proposed so far

Page 35: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

FINALLY IS THE SOLUTION THIS ONE?FINALLY IS THE SOLUTION THIS ONE?

Radio Loud AGNRadio Loud AGN

Radio Quiet AGNRadio Quiet AGN

Page 36: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Hawley, Balbus, 2002

OR ARE THE WIND AND THE JET COEXISTING?OR ARE THE WIND AND THE JET COEXISTING?

inner jets can be undetected in luminous AGNinner jets can be undetected in luminous AGN

WINDJET

Page 37: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

CONCLUSIONCONCLUSION

3. BAD NEWS:3. BAD NEWS: Only a small proportion of luminous AGN have Only a small proportion of luminous AGN have relativistic jets and non-thermal radiationrelativistic jets and non-thermal radiation

1. jets or high energy mechanisms can escape detection, if they 1. jets or high energy mechanisms can escape detection, if they are quenched close to the BHare quenched close to the BH

4. GOOD NEWS:4. GOOD NEWS: In low luminosity AGN (and basically all In low luminosity AGN (and basically all galaxies), jets and high energy processes take place close to galaxies), jets and high energy processes take place close to the central BHthe central BH

2. Jets in radio loud high luminosity AGN are likely driven by 2. Jets in radio loud high luminosity AGN are likely driven by spinning black holes, but other mechanisms must play a role spinning black holes, but other mechanisms must play a role

AND FINALLY, VERY LITTLE IS YET UNDERSTOOD!AND FINALLY, VERY LITTLE IS YET UNDERSTOOD!

Page 38: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Page 39: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

An exemple of a strong accretor (Ton S 180) modeled by a thick disk, An exemple of a strong accretor (Ton S 180) modeled by a thick disk, M(BH)=6 10M(BH)=6 1066 M Moo, m=60 , m=60

Kawaguchi, Piérens, Huré, 2003Kawaguchi, Piérens, Huré, 2003

Page 40: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Caution: one defines sometimesCaution: one defines sometimes

M•

Edd = LEdd /εc 2, which gives M•

Edd = M•

crit /10 for ε = 0.1

M•

Edd = LEdd /εc 2, which gives M•

Edd = M•

crit /10 for ε = 0.1

Page 41: Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

Blois 2008

Wind driving mechanismWind driving mechanism

-radiation pressure driven from the diskradiation pressure driven from the disk

but « shielding » of the central source necessarybut « shielding » of the central source necessary

-centrifugally driven from disks threated by an open magnetic fieldcentrifugally driven from disks threated by an open magnetic field

- thermally or hydrodynamically driven from the hot corona- thermally or hydrodynamically driven from the hot corona

sketch of a sketch of a disk wind, disk wind,

centrifugally centrifugally and/or and/or

radiatively radiatively acceleratedaccelerated


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