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Rob Fender (Southampton)

Are AGN ‘just’ scaled-up stellar-mass black holes?. Rob Fender (Southampton)

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Rob Fender (Southampton)

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  1. Are AGN ‘just’ scaled-up stellar-mass black holes? Rob Fender (Southampton) + Guy Pooley, Elena Gallo, Simone Migliari, Elmar Koerding, Sebastian Jester, Stephane Corbel, Ralph Spencer, Dave Russell, Valeriu Tudose, Catherine Brocksopp, Christian Kaiser, Tomaso Belloni, Jeroen Homan, Sera Markoff, Paolo Soleri, Tom Maccarone, James Miller-Jones, Clement Cabanac, Robert Dunn, Martin Bell…

  2. The importance of black hole accretion in the universe 6<z<14 first ‘AGN’ reionize universe 1<z<6 peak of AGN activity: feedback regulates galaxy growth, reheats cooling flows, creates X-ray background z<1 AGN accretion rates drop, accretion luminosity of universe dominated by binaries, jets dominate radiation

  3. Scaling black hole accretion with mass (naively!) M / R = const  constant accretion efficiency BUT density and temp very different

  4. When jets are formed (patterns of radio:X-ray coupling)

  5. Patterns of outbursts in the Hardness-Intensity diagram 600 day outburst of the black hole GX 339-4 in 60 seconds Data from Homan & Belloni (2006) Cause: disc instability cycle (probably) ~30% Eddington

  6. Belloni, Corbel, Fender, Gallo, Hanke, Kalemci, McHardy, Maitra, Markoff, Nowak, Petrucci, Pottschmidt, Wilms

  7. Do AGN behave anything like this ? Belloni, Corbel, Fender, Gallo, Hanke, Kalemci, McHardy, Maitra, Markoff, Nowak, Petrucci, Pottschmidt, Wilms

  8. Relation to AGN: what would an ensemble of X-ray binaries look like … ? Same source, different outburst… Different source… But the X-ray HID is no good for AGN, because their discs are cooler and peak at lower frequencies – need a more physically meaningful method of comparison

  9. The Disc Fraction Luminosity Diagram (DFLD): Koerding, Jester & Fender (2006) Simulated ensemble of X-ray binaries (Colour scale is radio loudness) SDSS quasars + LLAGN All disc All power-law

  10. The real ensemble of BH X-ray binaries (Dunn, Fender et al. in prep) >10 000 points – equivalent to a large AGN sample We do not have radio loudness for the vast majority of these points… .. but with the new generation of radio observatories (SKA pathfinders) we will get these and be able to make direct comparison with AGN

  11. Marscher et al. suggest 3C120 is behaving like XRB GRS 1915+105 with ejections associated with X-ray colour changes

  12. GRS 1915+105: black hole accretion at ~Eddington  unstable, quasi-periodic state changes and jet formation One hour of (patchy) data on GRS 1915+105, persistently accreting at ~Eddington ‘State’ changes can be as rapid as seconds (apparent disc radius changes faster than the viscous timescale) Is this what’s happening in the most luminous AGN? This side sensitive to disc This side sensitive to power-law This movie is sped-up by 60x

  13. Perhaps timing properties are a better tracer of ejection? Dips (‘zones’) of low variability Gradual state transition Ejection of the corona ? Fender, Homan & Belloni (in prep)

  14. The power of jets

  15. zoom out x 50 000: jet-ISM interaction (external shock over 106 years) (WSRT) Hard state jet (steady state) (VLBA) zoom out x 10: transient jet at state change (internal shock over several hours) (MERLIN) Cygnus X-1: a jet-blow bubble  calorimeter for jet power (Stirling et al. 2001; Fender et al. 2005; Gallo et al. 2006)

  16. Optical confirmation of shocked nebula Russell, Fender et al. (2006, 07) H-alpha and O[III] Line-emitting nebula.  Narrow bowshock with high O[III]:Halpha ratio Analysis indicates LJET ~ LX (at Eddington ratio of ~0.02) Blue = V-band Red = Hα [O III] / Hα Green = [O III] (500.7nm)

  17. Calibrating core radio luminosity to accretion rate for X-ray binaries Lradio a m1.4 (as predicted for Ljeta m) Koerding, Fender & Migliari (2006) . .

  18. . Then if we can rely on LRADIO calibration, we can see how LX varies with m . Up here LJET ~ LX and falls off linearly with m Direct evidence for radiatively inefficient accretion and jet-dominated states (with advection…) (X-ray luminosity) LJET LX Koerding, Fender & Migliari (2006) (mass accretion rate calculated from Lradio)

  19. ‘Fundamental’ plane(s) (Quantitatively linking X-ray binaries and AGN)

  20. Merloni, Heinz & di Matteo (2003) Falcke, Koerding & Markoff (2004) The ‘fundamental plane’ of black hole activity

  21. What does the fundamental plane mean ? if [a] Lradio a m1.4 (which we’ve just shown) and [b] LX/LEdd a (m/mEdd)2 LX / M a (m / M)2 (which is a general approximate solution for radiatively inefficient accretion where the accretion flow knows what Eddington ratio its at…) then simple re-arranging gives us: Lradio a LX0.7 M0.7 (c.f. LX0.6 M0.8fit)  The fundamental plane is almost perfectly recovered (extra tweaks required at the level of +/- 0.1 in power law indices) This implies that the plane is dominated by radiatively inefficient sources which are jet-dominated (and that hard  soft state transitions do not have a strong dependence on M, both in agreement with Koerding, Fender & Migliari 2006) . . . . .

  22. X-ray power spectra In XRBs break frequency correlates with jet power (Migliari, Fender & van der Klis 2006) .. and scaling with AGN is approximately linear in M (McHardy et al. 2006) … so….. Fourier transform of X-ray lightcurve

  23. Fundamental plane #2 ! • Tbreak ~ M2 / L • Tbreak ~ M / (m / mEdd) . . AGN XRBs McHardy, Koerding, Knigge, Uttley & Fender (Nature, 2006); Koerding et al. (2007)

  24. Accretion disc radii as a function of luminosity ~0.1 Edd This line is the slope predicted by the timing plane Rinner a L-1/3bol Hysteretical Zone ~10-3 Edd ~10-5 Edd Hard State ~10-7 Edd Lbol ~ISCO ~100 ISCO Cabanac, Fender et al. (in prep) (RG)

  25. So what do these planes mean ? • The `fundamental plane’ means (we think) that • all black holes produce the same amount of kinetic power output (jet) per unit mass of accreted material • the radiation produced is a function of Eddington ratio (the ratio of accretion rate to the maximum rate), so for a given accretion rate in kg, more massive black holes produce less radiation (unless you’re at or close to Eddington limit) • The new `timing’ plane seems to mean that • variability timescales depend linearly (as expected) with black hole mass, and inversely on accretion rate (in Eddington units) •  We have found extremely simple scalings between objects differing in both mass and accretion rate by eight orders of magnitude !

  26. Beware of cheap imitations (or: who needs an event horizon)

  27. Neutron stars and White Dwarfs do it too radio flare Radio flaring and hysteretical patterns observed from Cataclysmic Variable SS Cyg (Koerding et al. 2008)

  28. Conclusions: • Patterns: the qualitative relation between spectral states and jet production may be independent of black hole mass • Planes: Jet power and mass accretion rate may be quantified as a function of radio luminosity, and demonstrate jet-dominated advective states are the norm • plane #1 Lradio a LX0.6 M0.8 ( LJet a m a (LX/LEdd )0.5 ) • plane #2 Tbreak a M / (m/mEdd) • … so everything looks simple as long as you’re happy that accretion flows know what Eddington ratio they are at…. • What next ? we can use patterns from XRBs to estimate e.g. the kinetic luminosity function of Active Galactic Nuclei (Koerding, Jester & Fender 2008  LLAGN dominate kinetic feedback in local universe) • Even though the scaling laws are very nice, beware of attributing any of the propertes of the ‘disc jet’ coupling to specific physical properties of black hole… . . .

  29. … and there are of course differences between AGN and X-ray binaries Environment AGN are in a messy environment that is both: Extrinsic (wide distribution of temp, density, angular momentum in the fuel supply – very different to nearly all binaries), and Intrinsic (broad line region  X-ray binaries don’t launch line-driven winds from inner disc) These effects result in obscuration, modification of spectra, and – possibly – different outburst cycles Spin ? AGN and X-ray binaries may have a different distribution of black hole spin (but NB there is no direct evidence yet that spin strongly affects jet) THE END

  30. The jets may be just as relativistic as those from AGN XRB AGN (Jorstad) Miller-Jones, Fender & Nakar (2006) • What we don’t know very well • How fast the jets are

  31. LRADIO is not particularly fundamental, being less than 10-4 of LJET … … but we now know how to calibrate it to jet power and accretion rate…. Koerding, Fender & Migliari (2006)  So we can calibrate the fundamental plane…

  32. Fundamentaler and fundamentaler… 4 x 1044 4 x 1024 (jet power erg/sec) 1 x 1041 (mass accretion rate g/sec) 1x 1021 4 x 1037 4 x 1017

  33. X-ray binaries Do we know how the jets are formed ? No Do we know when (in terms of accretion state) and how much power ? Yes (approximately)

  34. XRB:AGN similarities… not a new idea Observed BH mass range 5 MO < MBH< 109 MO Shakura & Sunyaev (1976) and other disc models realised that accretion onto black holes might scale in a simple way Pounds, Done & Osbourne (1995) suggested Seyfert X-ray emission was like the soft state of galactic BHC Sams, Eckart & Sunyaev (1996) discussed scaling of BH jets with mass Falcke & Biermann (1995, 96, 99…): jet-disc ‘symbiosis’ Mirabel & Rodriguez (1992, 94, 99): ‘microquasar’ Heinz & Sunyaev (2002) calculated detailed scalings for jets

  35. McHardy et al. (2006) Timing plane Koerding et al. (2007) Extended timing plane – includes

  36. How do the plane and states relate to each other? For a given mass, this part results in the plane… Introduce a range of masses  a very broad plane The lack of very large deviations from the plane indicates transitions to radiatively efficient, jet-quiet states occurs in the same small range of Eddington ratios (ie. 0.01 < L < 1) for all black hole mass .. and this part results in small deviations from the plane

  37. What information do we get from this ? There is a ‘hard state’ in which the source begins and finishes the outburst There is a ‘soft state’ which only occurs at high X-ray luminosity There is hysteresis

  38. Cir X-1 … and, we have observed highly relativistic (Lorentz factor >10 !!) jets from neutron stars too (Fender et al. 2004) … That was an outburst of the neutron star X-ray binary Aql X-1 … (Maitra & Bailyn 03)

  39. What is the relation to jet formation ? Here we see a steady jet (LR a LX0.7) Here we see major ejections Here we see no jet jet behaviour (like other properties) is hysteretical with luminosity

  40. Hard state: Lradioa LX0.7 Apparent tightness of this correlation for different sources probably means G<2 Soft State LX (Edd) Gallo, Fender & Pooley (2003) Gallo, Fender et al. (2006) Gallo, Fender & Pooley (2003) Gallo, Fender et al. (2006)

  41. (slightly controversial!) What is the relation to the accretion disc ? As source fades in the hard state the accretion disc recedes In fading soft state disc cools at or close to L a T4 i.e. a black body with fixed size

  42. Accretion disc temperature in soft state Disc T (keV) (Dunn et al. in prep)

  43. Accretion disc radii as a function of luminosity ~0.1 Edd Hysteretical Zone ~10-3 Edd ~10-5 Edd Hard State ~10-7 Edd Lbol ~ISCO ~100 ISCO Cabanac et al. (in prep)

  44. Towards a unified model… More powerful, hard sources have more powerful, steady jets… As source softens, jet velocity increases abruptly, causing internal shock in jet Only crossing the ‘jet line’ from hard to soft makes an outburst !! Subsequently, soft states show no jet Faint, hard source have steady, G~1 jets Crossing from soft to hard (e.g.  quiescence) there is no shock Fender, Belloni & Gallo (2004)

  45. Why we expect black hole accretion to be essentially scale free: • The extreme mathematical simplicity of black holes: • Physical size scales linearly with black hole mass • M / R is the same (within a factor of a few, depending on spin) for all black holes – no other object in the universe scales so perfectly. The only other parameter is spin ( ‘giant elementary particles’) • Why we do not expect black hole accretion to be essentially scale free: • Microphysics ! The matter at the inner edge of an X-ray binary accretion disc is much hotter and much denser than that in an accretion disc around a supermassive black hole… (and who knows about conditions in magnetic field) • (and certainly neutron star and white dwarf accretion should be much messier, with solid surfaces, central dipole fields etc)

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