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5GHz, VLA image of Cyg A by R. Perley
Cosmological growth of SMBH:Cosmological growth of SMBH:the kinetic luminosity function of AGNthe kinetic luminosity function of AGN
IAU Symposium 238IAU Symposium 238 – PraguePrague 22/08/200622/08/2006
Andrea MerloniMax-Planck Institute for Astrophysics
&Sebastian Heinz
MIT
• Observed correlations (M-, Magorrian): How do they evolve at high redshift?
• Constraints on structure formation
• Constraints on feedback models (“radio mode” vs. “quasar mode” in the cosmologists jargon)
• What is the Kinetic Luminosity function of AGN, and how does it evolve?
• Need to include knowledge of accretion physics
Intro: Key questions
• Observed correlations (M-, Magorrian): How do they evolve at high redshift?
• Constraints on structure formation
• Constraints on feedback models (“radio mode” vs. “quasar mode” in the cosmologists jargon)
• What is the Kinetic Luminosity function of AGN, and how does it evolve?
• Need to include knowledge of accretion physics
Intro: Key questions
• Observed correlations (M-, Magorrian): How do they evolve at high redshift?
• Constraints on structure formation
• Constraints on feedback models (“radio mode” vs. “quasar mode” in the cosmologists jargon)
• What is the Kinetic Luminosity function of AGN, and how does it evolve?
• Need to include knowledge of accretion physics
Intro: Key questions
• Low accretion rate systems: X-ray radio correlation in binaries (Gallo et al. 2003, Fender 2005) jets/outflows dominate over radiation as power sinks. But is radiative efficiency low with respect to the accreted mass?
• Advection vs. Outflows
• What is the physics of Radio-Loud high accretion rate systems (QSOs)?
• What fraction of the power do the most powerful jets carry?
• How common are they (lifetime of the radio active phase)?
Open questions in accretion theory
• Low accretion rate systems: X-ray radio correlation in binaries (Gallo et al. 2003, Fender 2005) jets/outflows dominate over radiation as power sinks. But is radiative efficiency low with respect to the accreted mass?
• Advection vs. Outflows
• What is the physics of Radio-Loud high accretion rate systems (QSOs)?
• What fraction of the power do the most powerful jets carry?
• How common are they (lifetime of the radio active phase)?
Open questions in accretion theory
Heinz and Sunyaev 2003; Merloni et al 2003; Heinz 2004
• Compact, self-absorbed synchrotron emission from the jet core
• Assume jet power LKin~ Accretion rate
• Independent of geometry and jet acceleration mechanisms, it can be shown that LR~M17/12mdot17/12 for flat radio spectra
• The observed radio-X-ray correlation (LR~LX0.7) implies:
• X-ray emission is radiatively inefficient (LX~Mdot2)
• LKin ~ LR1.4
Scaling relations and the low/hard state
Heinz and Sunyaev 2003; Merloni et al 2003; Heinz 2004
• Compact, self-absorbed synchrotron emission from the jet core
• Assume jet power LKin~ Accretion rate
• Independent of geometry and jet acceleration mechanisms, it can be shown that LR~M17/12mdot17/12 for flat radio spectra
• The observed radio-X-ray correlation (LR~LX0.7) implies:
• X-ray emission is radiatively inefficient (LX~Mdot2)
• LKin ~ LR1.4
Scaling relations and the low/hard state
No evidence for break in correlation down to about 10-9 LEdd
Gallo et al. 2006
A0620 in quiescence: a unique tool
• The radiative inefficiency of the source (from comparing outer accretion rate with luminosity) and the slope of LR-LX correlation imply (Merloni, Heinz and Di Matteo 2003)
Ejet,Q
~ 5 1044 W ergs
Eoutburst
~ 2-4 1044 ergs
Gallo et al. (2006); Heinz and Grimm (2005)
A0620 in quiescence: does the jet take all?
• Verify the hypothesis that AGN at low luminosity release most of their power as Kinetic Energy and the Low-hard state scaling
• Need independent measures of LKin and LR (and/or LX, MBH)
• Dynamical, from models of jet/lobe emission and evolution
•Cyg A, M87, Perseus A
• Indirect, from estimates of PdV work done on sourrounding gas (X-ray cavities) (Allen et al. 2006; Rafferty et al. 2006)
What about radio galaxies and AGN?
Core Radio/X-ray correlation in AGN
5LX/LEdd
LR/LEdd1.4
Merloni et al. 2003; Maccarone et al. 2003.
Open triangles: BH binairesClosed squares: AGN
• Verify the hypothesis that AGN at low luminosity release most of their power as Kinetic Energy and the Low-hard state scaling
• Need independent measures of LKin and LR (and/or LX, MBH)
• Dynamical, from models of jet/lobe emission and evolution
•Cyg A, M87, Perseus A
• Indirect, from estimates of PdV work done on sourrounding gas (X-ray cavities) (Allen et al. 2006; Rafferty et al. 2006)
What about radio galaxies and AGN?
Merloni & Heinz, in prep.
Core Radio/LKin correlation in AGN
Cyg A, Carilli & Barthel ‘97
Per A, Fabian et al. 2002
M87, Bicknell & Begelman ‘96
Allen et al. 2006
Rafferty et al. 2006
L kin=6×1037 (L R
/1030 )0.7
• Derive the intrinsic, un-beamed core radio luminosity function of AGN from the observed flat spectrum radio sources LF (Dunlop & Peacock 1990).
• Assumes radio jets have all the same Gamma factor (or a distribution peaked around a single value)
• Use the LR/LKin relation to estimate kinetic power in low state objects
• Assume that 10% of high state objects are radio loud with Lkin~Lbol
(Merloni 2004; Heinz, Schwab & Merloni 2006; Merloni et al. 2006)
The Kinetic Luminosity Function of AGN
• Estimate accretion rate onto the black hole and kinetic energy output for any given LR-LX-MBH combination
• Solve continuity equations for BH growth (Small and Blandford 1992; Marconi et al. 2004) backwards in time, using the locally determined BH MF as a starting point
(Merloni 2004; Heinz, Schwab & Merloni 2006; Merloni et al. 2006)
Kinetic Luminosity Function of AGN: Evolution
Kinetic Energy output and SMBH growth
Energy budget
~ 83-90 %
~ 2-3 %
~ 9-16 %
~ 4-11 %
Merloni & Heinz, in prep.
• Constraints on the physics of accretion/jet production are crucial for our understanding of feedback
• “Low-luminosity AGN” are most likely dominated by kinetic energy as a sink of energy
• Physically motivated scaling Lkin ~ Lcore,5GHz0.7
• The redshift evolution of SMBH mass, accretion rate and kinetic energy output function can be determined from the joint evolution of X-ray and Radio AGN luminosity functions using the mass-L
X-L
R
relationship
• The K.E. feedback from LLAGN jets at late times starts dominating high mass objects first and then objects of progressively lower mass (downsizing of feedback)
• The occurrence of the so-called “radio mode” of AGN feedback is in fact only determined by accretion physics
Conclusions
Transient Black Hole Accretion
Belloni and Homan (2005)GX 339-4
(2002/03 outburst)
“Jet line”
giant radio flares
Compact radio jets
A0620-00 (V616 Mon)• In 30 years, IR/Optical/UV campaign have revealed
system parameters to a high level of accuracy:
• D = 1.2 ± 0.4 Kpc
• M = 11.0 ± 1.9 M๏
• 0.7 M ๏K3-K4V companion in a 7.75 hr orbit
• Optical accretion disc spectra and total energy released in outburst have been used to estimate the outer disc accretion rate of ~1-3 × 10-10 M ๏ /yr (about 5 orders of mag. larger than that onto BH if accretion efficient; McClintock et al. 1995; Meyer-Hofmeister & Meyer 1999)
2005 campaign: X-ray radio observations
Radio Flux density 51.1 μJy/beam (7.3σ)
Lowest reported for an X-ray binary so far
LR=7.5±3.7 × 1026 erg/s
–2-10 keV Luminosity (D=1.2 kpc)
–LX=7.1+3.4-4.1 x 1030 erg/s
On the origin of radio emission
• Typical radio luminosities of early-to-mid type K stars is in the range 1 × 1014 up to 3 × 1015 erg/s/Hz (factor of 30 smaller than what observed in A0620-00)
• Unlikely optically thin radio flare, seen at much larger (outburst) luminosity and/or larger scales
• Free-free emission unlikely, as would imply too large mass loss
• ADAF predictions fall short by more than 3 orders of magnitude
• Likely, continuous, persistent relativistic outflow with flat spectrum as seen in low/hard state sources