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Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

AGN, MASSIVE BLACK HOLES, ACCRETION. OR. ARE AGN FACTORIES OF HIGH ENERGY PARTICLES AND PHOTONS?. Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon. THE CONTEXT. STRONG AND WEAK ACCRETORS. DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDS. CONCLUSION. THE CONTEXT.

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Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

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  1. AGN, MASSIVE BLACK HOLES, ACCRETION OR ARE AGN FACTORIES OF HIGH ENERGY PARTICLES AND PHOTONS? Suzy Collin-Zahn LUTH, Observatoire de Paris Meudon

  2. THE CONTEXT STRONG AND WEAK ACCRETORS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDS CONCLUSION

  3. THE CONTEXT STRONG AND WEAK ACCRETORS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDS CONCLUSION

  4. RECALL OF SOME WELL-KNOWN FACTS Active Galactic Nuclei: from quasars (L=1046-48 erg/s) to Seyfert galaxies (L=1043-46 erg/s), and Low Luminosity AGN (L=1040-43 erg/s) 2. Power derived from accretion onto a supermassive black hole 3. BH present in ALL NUCLEI of galaxy, M(BH) from L=1010 to 105 M , M(BH) ~ M(Bulge)/1000 4. « Unified Scheme »

  5. Narrow line region Broad line region Accretion disk Black hole radio galaxies LINERs Absorbing torus (RL or RQ) Wind (FRI) (FRII)

  6. Faranoff-Riley, 1974 MILLIONS OF LIGHT-YEARS

  7. SOME FIDUCIAL VALUES gravitational radius:=1.5 1013M8cm ~10-5 pc Eddington luminosity = 1.3 1046M8erg/s bolometric luminosity where is the accretion rate rmaximum radiation efficiency of mass-energy conversion 0.057 for a Schwarzschild BH, R(ISCO)=6Rg 0.3 for a maximally rotating Kerr BH, R(ISCO)~1Rg

  8. HOW TO FUEL BLACK HOLES? The angular momentum (GMR)1/2 must be transported outward! 1. At large distances (≥ 100pc) Major and minor mergers (quasars) Tidal interactions between galaxies (luminous Seyfert) Bars, bars within bars, nonaxisymmetric potentials (weak Seyfert) Dynamical friction of molecular clouds (LLAGN)… 2. At small distances (<1pc) « ACCRETION DISKS » local turbulent viscosity (MRI, possibly) or global transport of AM via an organized magnetic field? 3. At intermediate distances Still unknown! Gravitational instability?

  9. THE CONTEXT STRONG AND WEAK ACCRETORS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDS CONSLUSION

  10. In local Universe Luminous AGN : ~ 1% of all galaxies Low Luminosity AGN : ~ 40% of all galaxies The remainder 60%: dormant BH

  11. ACCRETION DISKS: INFLUENCE OF THE ACCRETION RATE

  12. A. STRONG ACCRETORS Spectral distribution of Seyfert and RQQ, no radio or gamma radiation, everything is thermal! thermal emission accretion hot corona thermal Compton dust cold accretion disk thermal Compton inverse Compton synchrotron Observations by Sanders et al. 1989

  13. I. Thin disks, H/R <<0.1, optically thick, emit the « Big Blue Bump » Seyfert II. « slim » disks, H/R ~0.1, optically thick, radiation pressure, emit the « Big Blue Bump » Quasars, Narrow Line Seyfert 1 (NLS1s) III. « Thick » disks, H/R~1, optically thick, radiation pressure, emit soft X-rays, photons cannot escape, thus Some low mass NLS1s (106-7Mo), in growing process

  14. CONTROVERSY ABOUT THICK DISKS Do these boulimic accretors exist? MHD simulations seems to show that if m >> 10 at large distance, strong outflows are expelled at smaller distance, and theaccretion rate on the BHremains limited at the Eddington value. .

  15. NO HARD X-RAYS ARE EXPECTED FROM THESE DISKS BUT proof of the presence of a hot medium emitting the hard X-rays whose emission is « reflected » by the disk MCG _6_30_15 Iron K line Intensity Fabian et al. 2006 Energy in keV Relativistic profile of FeK  the disk extends down to ~10Rg, and sometimes to ~1Rg  ISCO of a rapidly spinning BH

  16. The reflection model: radiatively coupled disk + corona Corona Compton-cooled by UV photons Disk heated by gravitational release AND X-rays Same radiation coupling, but more realistic model : disk + « magnetic flares » Done, Gierlinski , 2004

  17. B. WEAK ACCRETORS Optically thin, geometrically thick, hot (relativistic) disks, emitting mainly radio and X-rays, Gas falls into the BH before radiating, thus  LLAGN, radio galaxies FRI (M87..), Galactic Center

  18. Inflated codona, or… …suppression of the inner regions of accretion disk The « Big Blue Bump » does not exist

  19. CONTROVERSY ABOUT THESE DISKS Which model for these anorexic accretors? ADAF, ADIOS, CDAF… RIAF Is there also a jet?

  20. ADAF+JET FOR A « QUIESCENT » BH: THE GALACTIC CENTER . measured M~3 10-6 Mo /yr L (for ~0.1) should be ~ 1041 erg/s BUT measured L~ 1036 erg/sL/LEdd ~ 3 10-9,~ 10-6 Synchrotron and Inverse Compton by thermal electrons flaring quiescent Synchrotron and Inverse Compton by non-thermal electrons (jet or ADAF?) bremsstrahlung Yuan, Quataert, Narayan, 2003

  21. ~ 1 pc a Sgr A* Jet? F. Baganoff et al. 2003

  22. ADAF+JET MODEL FOR A FRI GALAXY L/LEdd ~ 3 10-4 ADAF Jet Wu, Yuan, Cao, 2008

  23. CONCLUSION: • BOTH STRONG AND WEAK ACCRETORS ARE RADIATIVELY INEFFICIENT DISKS MUST PRODUCE OUTFLOWS TO EVACUATE THEIR ENERGY

  24. THE CONTEXT STRONG AND WEAK ACCRETORS DICHOTOMY RADIO LOUD / RADIO QUIET OBJECTS AND JETS / WINDS CONCLUSION

  25. AGN are divided in « Radio Loud » (RL) and « Radio Quiet » (RQ) RLQ BLRG FRI RQQ SEYFERTS LINERS Sikora, Stawarz, Lasota, 2007

  26. With a complete sample of quasars (SDSS) Mc Lure, Dunlop 2004 R = Lradio(5GHz) / Lopt Number of RLQ are less than 10% of RQQ

  27. RADIO LOUDNESS DEPENDS ON THE EDDINGTON FACTOR FRI BLRG RLQ LINERS SEYFERTS RQQ Log(L/Ledd)

  28. RADIO LOUDNESS DEPENDS ON M(BH) FRI RLQ LINERS, SEYFERTS BLRG RQQ

  29. I. HIGH LUMINOSITY AGN DIFFERENCES BETWEEN RL AND RQobjects 1. Locally RL are exclusively in elliptical galaxies, RQ in spiral galaxies 2. RLs are associated with non-thermal relativistic collimated jets, RQs seem associated with thermal non-collimated winds (detected by Broad Absorption Lines and X-ray absorbers) 3. Several more subtile properties, not understood (i.e. intense FeII lines only in RQs) WHY?

  30. JETS VERSUS WINDS OBSERVATIONS Jets are launched at R ≤ 1000 Rg (VLBI) Winds are launched at R ≥ 10000Rg Jets have relativistic bulk velocities and are made of relativistic particles Winds have velocities from few hundreds km/s to c/10 and consist of warm (105-6 K) thermal gas

  31. W JET DRIVING MECHANISM Magnetic field is indispensable to explain extended jet acceleration: 1. Centrifugally driven flow 2. Extraction of the rotational energyof the BH: field connects the BH to the disk (Blandford-Znajek, 1977) Jets might be linked with the spin of the BH

  32. BLACK HOLE SPIN Measured by dimensionless angular momentum a = J/Jmax = cJ/GM2 1. Even RQ AGN have spinning BH (FeK line) 2. Cosmological evolution of AGN requires large fraction of spinning BHs (mass-conversion efficiency must be > 0.06) 3. Power of the jet must increase with a 4. It is expected that a increases with accretion AND with merger of two BHs 5. BHs increase with galaxy bulges, and a fraction of elliptical galaxies (large bulges) are due to the merger of spirals Elliptical galaxies favor high spin, therefore jets

  33. But it does not explain all: Other mechanisms must be at work 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: thick or thin 3. Density profile of the circumnuclear regions can play a role: cusp or core etc… etc…

  34. II. LOW LUMINOSITY AGN DO THEY HAVE JETS? YES! A sample of Low Luminosity AGN large M(BH)small M(BH) (bulge) Falcke et al; 2000 Compact jet structure with flat spectra observed in 40% of LLAGN but no detailed mechanism proposed so far

  35. FINALLY IS THE SOLUTION THIS ONE? Radio Quiet AGN Radio Loud AGN

  36. OR ARE THE WIND AND THE JET COEXISTING? WIND JET Hawley, Balbus, 2002 inner jets can be undetected in luminous AGN

  37. CONCLUSION 1. jets or high energy mechanisms can escape detection, if they are quenched close to the BH 2. Jets in radio loud high luminosity AGN are likely driven by spinning black holes, but other mechanisms must play a role 3. BAD NEWS: Only a small proportion of luminous AGN have relativistic jets and non-thermal radiation 4. GOOD NEWS: In low luminosity AGN (and basically all galaxies), jets and high energy processes take place close to the central BH AND FINALLY, VERY LITTLE IS YET UNDERSTOOD!

  38. An exemple of a strong accretor (Ton S 180) modeled by a thick disk, M(BH)=6 106 Mo, m=60 Kawaguchi, Piérens, Huré, 2003

  39. Caution: one defines sometimes

  40. Wind driving mechanism • radiation pressure driven from the disk • but « shielding » of the central source necessary • centrifugally driven from disks threated by an open magnetic field - thermally or hydrodynamically driven from the hot corona sketch of a disk wind, centrifugally and/or radiatively accelerated

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