ACCRETION JET CONNECTION τ α MBH

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1 Radio Observations

2 ACCRETION JET CONNECTION τ α MBH 1 hr in GRS = 30 yr in SgrA* Mirabel et al THE TRIGGERS OF JETS ARE INSTABILITIES IN THE ACCRETION DISK (TRANSITION LOW HARD TO HIGH THE X-RAY SPIKE MARKS THE ONSET OF A SHOCK THROUGH THE COMPACT, STEADY JET ANALOGOUS ACCRETION-JET CONNECTION IN 3C 120 Marscher (2002)

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4 Y VLA 27 Km VLBA MERLIN 150 Km

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6 COMPACT STEADY JETS GRS : Dhawan, Ribo & Mirabel (2006) 2.0 cm 3.6 cm ~100 AU IN LENGTH PRESENT DURING LOW HARD STATE SPEED OF THE FLOW < 0.4c (Dhawan, Ribo & Mirabel 2006)

7 SUPERLUMINAL MOTION IN THE GALAXY Mirabel & Rodriguez, RELATIVISTIC ABERRATION FROM TWIN JETS SEEN TWO-SIDED - µqso JETS MOVE ON THE SKY ~103 TIMES FASTER THAN QSO JETS - IN AGN AT D<100 Mpc JETS ARE RESOLVED AT ~50 Rsh (e.g. M87,Biretta) PHYSICS: NEED TO STUDY BHs ACROSS ALL MASS SCALES

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9 Superluminal Motion 0 Individual radio knots in quasar jets: Sometimes apparently moving faster than speed of light! Light-travel time effect: Material in the jet is almost catching up with the light it emits

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16 SUPERLUMINAL MOTIONS IN QSOs & AGN OBSERVED IN > 30 QSOs & AGN IN RADIO & OPTICAL WAVES PROPER MOTION SEEN IN YEARS Vapp UP TO 30c in blazars One sided because of Doppler boosting

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21 Relativistic electrons in a magnetic field E = γ me c 2 γ= 1 v2 1 2 c γ>>1 For one electron, max frequency γ2 for slightly different γ covers the entire spectrum Electron energy distribution is a power law: -p N E de =ke de Assuming the emission from each can be added up (optically thin case) υ /υ P υ, θ B p 1 /2 υ p 1 / υ /υ1 α The radio spectrum is therefore a power law: S υ α Typical α~0.8 α = p 1 /2 p~2.6

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23 N ( E )de = CE p de In this case, we have S (ν ) ν p 1 2

24 Flux density vs frequency

25 Longair

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27 Flux density (Jy)

28 TRANSIENT JETS GRS Optically thin spectra steep STEADY JETS Flat spectra Mirabel.& Rodrigez 1994 GRS Dhawan et al Fender 2001 Fender et al. 2001, 2004,2006 Steady Jets and Transient Jets- Bonn 2010 M. Massi

29 t The radio-optical spectrum of XRBs Radio-to-NIR spectrum is flat in the hard state. V404 Cyg (Fender 2000)

30 RADIO SPECTRUM: WHY IS IT FLAT? Sν νb r e a k ν

31 Dulk (1985), Ann. Rev. Astronomy & Astrophysics, 23, 183

32 Blandford & Konigl 1979; Hjellming & Johnston 1988; Falcke et al. 1996; Kaiser 2006; Pe'er &Casella 2009) Mbh~10 JET Sν νb r e a k Change of the plasma conditions along the jet: decay of the magnetic field change in the electron energy distribution

33 Mbh~10 1 Sν JET 1 1 ν dependence of the break frequency on the changing plasma conditions along the jet Blandford & Konigl 1979; Hjellming & Johnston 1988; Falcke et al. 1996; Kaiser 2006; Pe'er &Casella 2009

34 Rmin Mbh~109 Mbh~10 Rmin ν max~1015 Hz ν max~1013 Hz Sν Sν ~ ν-0.7 Sν Radio/mm Radio/mm Opt/UV/X ν turnover frequency in stellar black holes > blazars ( BXRB>>BAGN) ν

35 Steady Radio Jet slow velocity ~0.1 c Dhawan et al Continuous conical jet centered on the system, system flat radio spectrum

36 GRS Dhawan et al 2000

37 Two distinct radio emission states GRS radio emission attached to... and detached from the center GRS Dhawan et al GRS Mirabel.& Rodrigez 1994

38 TRANSIENT JETS Optically thin spectra steep STEADY JETS Flat spectra Dhawan et al Mirabel.& Rodrigez 1994 X-ray State X-ray State Steep Power-low State Low Hard Fender 2001 Fender et al Steady Jets and Transient Jets- Bonn 2010 M. Massi

39 Energy spectra from McClintock & Remillard (2006) Accretion states Photon cm-2 s-1 kev High (thermal dominated) ~ 1 2 kev disc + PL tail Energy (kev) Low/Hard Very High Hard PL (Γ ~ 1.5 2) (steep power-law) dominant, disc absent or truncated, radio jet Soft PL (Γ > 2.5) plus some hot emission. Least luminous. disc emission. Most luminous.

40 Distributions in Photon Index Ron Remillard Hard SPL Thermal

41 Radio/X-ray Flux Correlation Fradio FX+0.7 Corbel et al. (2000,2003)

42 Radio/X-ray Flux Correlation Fradio FX+0.7 Corbel et al. (2000,2003)

43 ~1.0 Transient X-ray Luminosity / Eddington ~0.1 ~0.01 Hardness ratio: the ratio of detector counts in two energy bands ( example. the ratio of source <10-6 soft counts at 6.3 hard spectrum spectrum 10.5 kev to hardness X-ray the counts at kev)

44 Powerful jets produced in transition from canonical low/hard to high/soft states Gallo et al Fender, Belloni & Gallo (2004) Gallo et al Homan & Belloni 2005 GX Fender.ppt

45 Black Hole States: Statistics Timescales (days) for state (all BH Binaries) duration Steep Power Law 1-10 Low/hard Ronald Remillard transitions <1 1-5

46 In analogy with solar flares, magnetic energy is probably built-up and accumulated over long time scales and then dissipated in very short time On the other hand the removal of angular momentum via the steady jet has a dramatic effect on the overall process of the accretion process, further increasing the twist of the magnetic field and making magnetic reconnection among tangled field lines likely to occur. TRANSIENT JET S T E A D Y J E T

47 Marscher & Gear shock-in-jet model (1985) Gallo et al Marc Türler Gallo et al New highly-relativistic plasma catches up the pre-existing slower-moving material of the steady jet giving rise to shocks... Marc Türler's review..that produce the optically thin outburst.