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…
Are AGN ‘just’ scaled-up stellar-mass black holes?
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
The importance of black hole accretion in the universe
Scaling black hole accretion with mass (naively!)
M / R = const constant accretion efficiency
BUT density and temp very different
When jets are formed
(patterns of radio:X-ray coupling)
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
Belloni, Corbel, Fender, Gallo, Hanke, Kalemci, McHardy, Maitra, Markoff, Nowak, Petrucci, Pottschmidt, Wilms
Belloni, Corbel, Fender, Gallo, Hanke, Kalemci, McHardy, Maitra, Markoff, Nowak, Petrucci, Pottschmidt, Wilms
Do AGN behave anything like this ?
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
(Colour scale is radio loudness)
The Disc Fraction Luminosity Diagram (DFLD): Koerding, Jester & Fender (2006)
Simulated ensemble of X-ray binaries
SDSS quasars + LLAGN
All disc All power-law
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
Marscher et al. suggest 3C120 is behaving like XRB GRS 1915+105 with ejections associated with X-ray colour changes
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 movie is sped-up by 60x
This side sensitive to power-law
This side sensitive to disc
Perhaps timing properties are a better tracer of ejection?
Ejection of the corona ? Fender, Homan & Belloni (in prep)
Dips (‘zones’) of low variability
Gradual state transition
The power of jets
Hard state jet (steady state) (VLBA)
Cygnus X-1: a jet-blow bubble calorimeter for jet power
(Stirling et al. 2001; Fender et al. 2005; Gallo et al. 2006)
zoom out x 10: transient jet at state change (internal shock over several hours) (MERLIN)
zoom out x 50 000: jet-ISM interaction (external shock over 106 years) (WSRT)
Optical confirmation of shocked nebula
H-alpha and O[III] Line-emitting nebula.
Blue = V-band
Red = Hα Green = [O III] (500.7nm)
Narrow bowshock with high O[III]:Halpha ratio
[O III] / Hα
Russell, Fender et al. (2006, 07)
Analysis indicates
LJET ~ LX
(at Eddington ratio of ~0.02)
Calibrating core radio luminosity to accretion rate for X-ray binaries
Lradio m1.4
(as predicted for Ljet m)
Koerding, Fender & Migliari (2006)
.
.
Koerding, Fender & Migliari (2006)
Then if we can rely on LRADIO calibration, we can see how LX varies with m
(mass accretion rate calculated from Lradio)
(X-r
ay lum
inosi
ty)
.
Direct evidence for radiatively inefficient accretion and jet-dominated states (with advection…)
Up here LJET ~ LX and falls off linearly with m.
LJET
LX
‘Fundamental’ plane(s)
(Quantitatively linking X-ray binaries and AGN)
Merloni, Heinz & di Matteo (2003) Falcke, Koerding & Markoff (2004)
The ‘fundamental plane’ of black hole activity
What does the fundamental plane mean ?
if [a] Lradio m1.4
(which we’ve just shown)
and [b] LX/LEdd (m/mEdd)2 LX / M (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 LX0.7 M0.7 (c.f. LX
0.6 M0.8 fit)
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)
.
.
. . .
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
Fundamental plane #2 !
Tbreak ~ M2 / L
Tbreak ~ M / (m / mEdd)
McHardy, Koerding, Knigge, Uttley & Fender (Nature, 2006); Koerding et al. (2007)
. .
XRBs
AGN
~0.1 Edd
~10-3 Edd
~10-5 Edd
~10-7 Edd
~ISCO ~100 ISCO
Accretion disc radii as a function of luminosity
Hard State
HystereticalZone
Cabanac, Fender et al. (in prep)
This line is the slope predicted by the timing plane RinnerL-1/3
bol
Lbol
(RG)
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 !
Beware of cheap imitations
(or: who needs an event horizon)
Neutron stars and White Dwarfs do it too
Radio flaring and hysteretical patterns observed from Cataclysmic Variable
SS Cyg
(Koerding et al. 2008)
radio flare
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 LX0.6 M0.8 ( LJet m (LX/LEdd )0.5 )
plane #2 Tbreak 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…
. .
.
… 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
What we don’t know very well
• How fast the jets are
The jets may be just as relativistic as those from AGN
XRB
AGN (Jorstad)
Miller-Jones, Fender & Nakar (2006)
LRADIO is not particularly fundamental, being less than 10-4 of LJET …
Koerding, Fender & Migliari (2006)
So we can calibrate the fundamental plane…
… but we now know how to calibrate it to jet power and accretion rate….
4 x 1017
1x 1021
4 x 1024
(mas
s ac
cret
ion
rate
g/s
ec)
Fundamentaler and fundamentaler…
4 x 1037
1 x 1041
4 x 1044
(jet power erg/sec)
X-ray binariesDo we know how the jets are formed ? No
Do we know when (in terms of accretion state) and how much power ? Yes (approximately)
XRB:AGN similarities… not a new ideaObserved 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
McHardy et al. (2006)Timing plane
Koerding et al. (2007)
Extended timing plane – includes
For a given mass,this part results in the plane…
.. and this part results in small deviations from the plane
How do the plane and states relate to each other?
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
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
That was an outburst of the neutron star X-ray binary Aql X-1 … (Maitra & Bailyn 03)
Cir X-1
… and, we have observed highly relativistic (Lorentz factor >10 !!) jets from neutron stars too (Fender et al. 2004) …
What is the relation to jet formation ?
Here we see a steady jet
(LR R L LXX0.70.7))
Here we see no jet
Here we see major ejections
jet behaviour (like other properties) is hysteretical with luminosity
Hard state: Lradio LX0.7
Gallo, Fender & Pooley (2003) Gallo, Fender et al. (2006)
LX (Edd)
Gallo, Fender & Pooley (2003) Gallo, Fender et al. (2006)
SoftState
Apparent tightness of this correlation for different sources probably means <2
What is the relation to the accretion disc ?
In fading soft state disc cools at or close to
L T4
i.e. a black body with fixed size
As source fades in the hard state the accretion disc recedes
(slightly controversial!)
Accretion disc temperature in soft state
Disc T (keV)(Dunn et al. in prep)
~0.1 Edd
~10-3 Edd
~10-5 Edd
~10-7 Edd
~ISCO ~100 ISCO
Accretion disc radii as a function of luminosity
Hard State
HystereticalZone
Cabanac et al. (in prep)
Lbol
Towards a unified model…
Faint, hard source have steady, ~1 jets
More powerful, hard sources have more powerful, steady jets…
As source softens, jet velocity increases abruptly, causing internal shock in jet
Subsequently, soft states show no jet
Only crossing the ‘jet line’ from hard to soft makes an outburst !!
Crossing from soft to hard (e.g. quiescence) there is no shock Fender, Belloni & Gallo (2004)
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)