Transcript Slides

Disk-Jet Connection
in the Radio Galaxies
3C 120 and 3C 111
Ritaban Chatterjee
YCAA Seminar, September 22nd, 2009.
1
Data Sources




X-Ray (RXTE-PCA) and VLBA: A. Marscher, S.
Jorstad (BU)
37 GHz : Anne Lahteenmaki, Merja Tornikoski,
Talvikki Hovatta (Metsahovi Observatory, Finland).
R Band: I. McHardy (U. Southampton), Kevin Marshall,
H. Richard Miller, Wesley T. Ryle (Georgia State)
V Band: Large international team (please see ApJ paper
for details) led by Martin Gaskell (U. Texas, Austin, U.
Nebraska, Lincoln).
2
AGN: Definition
“An active galactic nucleus
(AGN) is a compact region at
the center of a galaxy which has
a much higher than normal
luminosity over some or all of
the electromagnetic spectrum.
The radiation from AGN is
believed to be a result of
accretion on to a super-massive
black hole at the centre of the
host galaxy.”
-Wikipedia
3
AGN : Unified Picture
Blazar
BLRG
3C 120 and 3C 111
are BLRGs
Courtesy:
C.M. Urry
& P. Padovani
4
Mirabel &
Rodriguez 1998,
Nature, 392, 673.
5
OUTLINE
• Why time variability
• 3C 120, 3C 111: Characteristic timescale
• 3C 120, 3C 111: X-ray/optical production
mechanism(s) and location
• 3C 120, 3C 111: Accretion disk-jet connection
• Effect of these results on AGN-BHXRB
connection
• Future Plans
6
Why Time Variability?
7
Thesis Title

Multi-Frequency Time variability of Active
Galactic Nuclei
8
Alternative Titles
Reliable Information from Variable
Emission
 Variable Emission, Dependable Results
 Consistent Information from Variable
Emission: Multi-Frequency Time
Variability of Active Galactic Nuclei

9
3C 279
Optical (STScI DSS)
VLBA (BU blazar group)
3C 279
Z=0.536
1 mas = 6.3 pc
Gamma-Ray (CGRO team)
10
Use of Time Variability Analysis
Upper limit to physical size : R ≤ cΔt'
 Power spectral density (amplitude of
variability as a function of timescale) =>
periodicity, characteristic timescales
 Correlation and light curve decomposition
(Comparison of flux at different
wavelengths) => structure and emission
mechanism(s)

11
OUTLINE
• Why time variability
• 3C 120, 3C 111: Characteristic timescale
• 3C 120, 3C 111: X-ray/optical production
mechanism(s) and location
• 3C 120, 3C 111: Accretion disk-jet connection
• Effect of these results on AGN-BHXRB
connection
• Future Plans
12
3C 120
1. BLRG
2. FR-I
3. z=0.033
4. Angle between
jet axis and
line of sight
~20o
5 GHz Image: Walker, Benson & Unwin 1987 ApJ, 316, 546
13
3C 111
1. BLRG
2. FR-II
3. z=0.048
4. Angle between
jet axis and
line of sight
~20o
1.4 GHz Image: Linfield & Perley 1984, ApJ, 279, 60
14
Why 3C 120 and 3C 111?
15
Variability at
different
timescales
Power Spectral Density (PSD) =>
Amplitude of variability as a function
of timescale
16
X-Ray PSD of
Cygnus X-1 : Break
BH Mass vs. Break
Time Scale
Uttley et al. 2004, MNRAS
17
3C 120 X-Ray Power Spectral Density (PSD)
Break
Frequency
=10-5 Hz
Break
Time Scale
=2 Days
18
X-Ray PSD of
Cygnus X-1 : Break
BH Mass vs. Break
Time Scale
3C 120
Uttley et al. 2004, MNRAS, 348, 783
19
X-Ray PSD of
Cygnus X-1 : Break
BH Mass vs. Break
Time Scale
3C 111
3C 120
These radio galaxies have characteristic
timescales similar to the Galactic BH
systems => Accretion processes in a
large range of BH masses (10-108 Msun)
have similar properties
Uttley et al. 2004, MNRAS, 348, 783
20
Working on 3C 120 ! . . .
. . . Are you in
Craig Walker’s group?
21
OUTLINE
• Why time variability
• 3C 120, 3C 111: Characteristic timescale
• 3C 120, 3C 111: X-ray/optical production
mechanism(s) and location
• 3C 120, 3C 111: Accretion disk-jet connection
• Effect of these results on AGN-BHXRB
connection
• Future Plans
22
Light Curves of 3C 120 between 2002 and 2007
X-RAY
OPTICAL
RADIO
Chatterjee et al. 2009,
ApJ, in press
23
3C 120: X-ray/Optical Correlation
Chatterjee et al. 2009, ApJ, in press
24
Light Curves of 3C 111 between 2002 and 2007
X-RAY
OPTICAL
RADIO
Chatterjee et al. 2009,
in preparation
25
3C 111: X-ray/Optical Correlation
X-ray leads
Optical by
15±5 days
Chatterjee et al. 2009, in preparation
26
• Optical emission is blackbody radiation from
the accretion disk
• Thermal optical/UV seed photons are inverseCompton scattered to X-rays by hot electrons
in the corona
• Modeling of the accretion disk-corona system
27
Model of the Accretion Disk/Corona System
Chatterjee et al. 2009, ApJ, in press
28
X-ray and Optical
model flares
Disturbance is
propagating toward the
center
Disturbance is
propagating away from
the center
Chatterjee et al.
2009, ApJ,
in press
29
Feedback in Accretion Disk/Corona System
30
X-ray and Optical Model Flares (Including
Feedback)
31
OUTLINE
• Why time variability
• 3C 120, 3C 111: Characteristic timescale
• 3C 120, 3C 111: X-ray/optical production
mechanism(s) and location
• 3C 120, 3C 111: Accretion disk-jet connection
• Effect of these results on AGN-BHXRB
connection
• Future Plans
32
Movie Time!
33
Superluminal Ejections Follow X-ray
Dips in 3C 111
•X-rays are produced in
the accretion disk, radio
emission is from the jet
•Connection between Xray and radio emission =>
Connection between
accretion disk and jet
Chatterjee et al. 2009, in preparation
34
Possible Explanation of the X-ray Dip and
Superluminal Ejection Correlation
 Change in the magnetic field configuration in
the accretion disk from turbulent to aligned
 absence of viscous heating causes dips in Xray production
 aligned B field configuration facilitates shock to
move toward the jet (Livio et al. 2003)
Turbulent
Aligned
X-ray production
Weaker flow in the jet
Decrease in X-ray production
Increase in flow in the jet
35
OUTLINE
• Why time variability
• 3C 120, 3C 111: Characteristic timescale
• 3C 120, 3C 111: X-ray/optical production
mechanism(s) and location
• 3C 120, 3C 111: Accretion disk-jet connection
• Effect of these results on AGN-BHXRB
connection
• Future Plans
36
The next three slides are from:
Rob Fender, U. Southampton, UK.
37
The life and times of a black hole X-ray binary…
X-ray Luminosity / Eddington
~1.0
source gets
very bright
and ‘softens’
Outburst
~0.1
~0.01
source remains
soft for some
time then fades
away, returning
to hard X-ray
spectrum
<10-6
X-ray
soft
spectrum
hard
spectrum
after, typically,
10+ years of
relative peace,
accretion rate
increases
Quiescence
hardness
As source softens,
jet velocity increases
abruptly, causing
internal shock in jet
Subsequently,
soft states
show no jet
More powerful,
hard sources have
more powerful,
steady jets…
Faint, hard
source have
steady, ~1
jets
39
Luminosity / Eddington
Relation
to AGN ?
Bright, radioquiet AGN (with old lobes?)
~1.0
Bright,
Radio-loud
AGN
~0.1
~0.01
LLAGN
<10-6
<10-9
X-ray
Sgr A*
soft
hard
Quiescence
hardness
Fundamental Plane of BH Activity (edge-on view)
Merloni, Heinz
& Di Matteo
2003, MNRAS,
345, 1057
41
Conclusions
X-ray and optical emission from the
accretion disk/corona system
 Corona lies within ~50 gravitational radii
 Similar characteristic timescale in accreting
BH systems of masses 10-108 Msun
 Connection between accretion disk and jet
 Similarity with galactic black hole X-Ray
Binaries: Universality of BH systems

42
Future Plans
More detailed theory of the time variable
emission from the accretion disk-corona
system.
 Analysis and interpretation of X-ray binary
monitoring data from SMARTS.
 Gamma-ray variability of blazars using Fermi
data. Also related multi-wavelength data
including SMARTS.
 More detailed theory of the time variable
emission from blazar jets.

43
Time-Variability of
Active Galactic Nuclei
THE END
44
3C 120 X-Ray Power Spectral Density (PSD)
Break
Frequency
=10-5 Hz
Break
Time Scale
=2 Days
45
46
The Accretion-Disk/Corona
Complex
X-rays
corona
UV
accretion disk
BH
Simple modeling of the above system
47
Spectral Energy Distribution of 3C 279 :
Spanning 16 decades of Frequency
Courtesy:
Alan
Marscher
48
AGN : Schematic Model
Cartoon
courtesy:
Prof. Alan
Marscher
49
X-ray light
curve :
Sum of model
flares & real
data
Chatterjee et al. 2008
(ApJ, in press)
50
Optical light
curve :
Sum of model
flares & real
data
Chatterjee et al. 2008
(ApJ, in press)
51
Light Curve
Decomposition
Chatterjee et al. 2008, ApJ,
489, 79
52
Superluminal Ejections Follow X-ray
Dips in 3C 120
Chatterjee et al.
2009, ApJ,
in press
53
Superluminal
Ejections Follow
X-ray Dips in
3C 120
Chatterjee et al.
2009, ApJ,
in press
54
X-ray/37 GHz Anti-correlation
(X-ray leads 37GHz by 120 days)
Chatterjee et al.
2009, ApJ,
in press
55
Possible Explanation of the X-ray Dip and
Superluminal Ejection Correlation
 Corona is the base of the jet
 decrease in the number density of
electrons at the base of the jet
 causes decrease in X-ray production
 increase in the speed of particles
(continuity eqn.) => shock wave.
56