Upload
vuongthuy
View
214
Download
0
Embed Size (px)
Citation preview
Connections between Radio and High Energy
Emission in AGN
1
Geoff BicknellResearch School of Astronomy & Astrophysics
Australian National University
Friday, 27 July 12
COSPAR 2012
Collaborators:
2
• Loredana Bassani, INAF, Bologna
•Nadine Neumayer, ESO, Munchen
• Francesca Panessa, INAF, Roma
• Ralph Sutherland, RSAA
• Andrea Tarchi, INAF, Cagliari
• Alex Wagner, Tsukuba University
Friday, 27 July 12
COSPAR 2012
Motivation:
3
Disk emission
Coronal emission / Advection Dominated Accretion Flows (ADAFs)
Jets and Winds
* Parameters of jets in radio-loud objects close to black hole
* Launching of jets from black holes
* Partition of Black Hole Gravitational Power into:
Friday, 27 July 12
COSPAR 2012
Origin of X-ray emission
4
Two main possible emission mechanisms:
• Comptonization of soft disk photons by hot corona
• Synchrotron or Inverse Compton emission from jet
Radio loud: Predominantly flat spectral index
Radio quiet: Predominantly steepspectral index
Shastri et al. ’93
Friday, 27 July 12
COSPAR 2012
Black Hole Fundamental Plane
5
Merloni & Heinz ’03Falcke ’04
5 GHZ core luminosity vs2-10 keV luminosity
log LR = 1.05 log LX + 0.78 log M + 7.33
Offset in Galactic and Extragalactic correlations due to black hole mass
Friday, 27 July 12
COSPAR 2012
Panessa et al 2007
6
Low luminosityRadio Galaxies
Seyfert galaxies(radio quiet)
Difference of 3 orders of magnitude in radio luminosity but same slope
LX / L0.97R
Friday, 27 July 12
COSPAR 2012
Panessa et al. 2011 - Correlation lost at VLBI resolution
7
VLA core
VLBI core
Suggests correlation with jet power rather than luminosity
Friday, 27 July 12
COSPAR 2012
INTEGRAL Sample
8
INTEGRAL 20-40 keV sample; 88 sources (Malizia et al. ’09)
2-10 keV X-ray data (Malizia et al. + literature)
NVSS radio data (Maiorano et al. in prep.)
20-100 keV
Friday, 27 July 12
COSPAR 2012
Different modes of X-ray and radio emission
9
• Disk and corona dissipate gravitational power rapidly
• Jet Poynting flux-dominated, non dissipative
• Jet power manifest on kpc scales
Corona
Gamma-ray and/or X-ray emission region
Jet
Chaotic magnetic field
Wind
Shock orreconnectionregion
Ordered magneticfield
Friday, 27 July 12
COSPAR 2012
Relationship between radio power and jet power
10
Not simply a conversion of jet power into luminosity
Model-dependent, e.g. Shabala et al. ’05: Expansion of radio source into 2-component background medium
Model for Seyferts motivated by observations of NGC 4051
Friday, 27 July 12
COSPAR 2012
NGC 4051: Giroletti & Panessa ’09
11
~ 19 kpc bubble on large scales fed by jet on small scales
Friday, 27 July 12
COSPAR 2012
Jet – Interstellar Medium interaction
12
Density Powerful 1045 ergs s-1 jet in 1 kpc fractal medium
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
K estimated from electron pressure
K ⇡ 3ptot
mec2
✓pe
ptot
◆�(a�2)
1
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
K estimated from electron pressure
K ⇡ 3ptot
mec2
✓pe
ptot
◆�(a�2)
1
Lower cutoff
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
Radius and pressure of bubble
R = At3/5
ptot
=1225
⇢aA2t�4/5
A =
125384⇡
FE
⇢a
�1/5
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
K estimated from electron pressure
K ⇡ 3ptot
mec2
✓pe
ptot
◆�(a�2)
1
Lower cutoff
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
Radius and pressure of bubble
R = At3/5
ptot
=1225
⇢aA2t�4/5
A =
125384⇡
FE
⇢a
�1/5
Ambient density
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
K estimated from electron pressure
K ⇡ 3ptot
mec2
✓pe
ptot
◆�(a�2)
1
Lower cutoff
Friday, 27 July 12
COSPAR 2012
Luminosity of bubble
13
Radius and pressure of bubble
R = At3/5
ptot
=1225
⇢aA2t�4/5
A =
125384⇡
FE
⇢a
�1/5
Ambient density
Jet energy flux
j⌫ = Numerical Factors⇥ K B(a+1)/2 ⌫�(a�1)/2
N(�) = K��a
Emissivity
K estimated from electron pressure
K ⇡ 3ptot
mec2
✓pe
ptot
◆�(a�2)
1
Lower cutoff
Friday, 27 July 12
COSPAR 2012
Luminosity - Jet Power relation
14
P⌫ = j⌫ ⇥Volume
B = Equipartition with total pressure
Friday, 27 July 12
COSPAR 2012
Luminosity - Jet Power relation
14
P⌫ = j⌫ ⇥Volume
B = Equipartition with total pressure
P⌫ ⇡ Numerical Factor⇥ ⇢3(a+1)/20a F (a+11)/10
E t(4�a)/5⌫(3�a)/2
Friday, 27 July 12
COSPAR 2012
Luminosity - Jet Power relation
14
P⌫ = j⌫ ⇥Volume
B = Equipartition with total pressure
P⌫ ⇡ Numerical Factor⇥ ⇢3(a+1)/20a F (a+11)/10
E t(4�a)/5⌫(3�a)/2
na ⇠ 1 cm�3
Friday, 27 July 12
COSPAR 2012
Luminosity - Jet Power relation
14
P⌫ = j⌫ ⇥Volume
B = Equipartition with total pressure
P⌫ ⇡ Numerical Factor⇥ ⇢3(a+1)/20a F (a+11)/10
E t(4�a)/5⌫(3�a)/2
t ⇠ 3⇥ 108 yrna ⇠ 1 cm�3
Friday, 27 July 12
COSPAR 2012
Luminosity - Jet Power relation
14
P⌫ = j⌫ ⇥Volume
B = Equipartition with total pressure
P⌫ ⇡ Numerical Factor⇥ ⇢3(a+1)/20a F (a+11)/10
E t(4�a)/5⌫(3�a)/2
t ⇠ 3⇥ 108 yrna ⇠ 1 cm�3
INTEGRAL sample: ⌫ = 1.4 GHz
Friday, 27 July 12
COSPAR 2012
Radio power -> Luminosity
15
Strongest dependence is on energy flux
P⌫ / F (a+11)/10E
) FE / P 10/(a+11)⌫ = P 0.76
⌫ for a = 2.2
Friday, 27 July 12
COSPAR 2012
Energy flux – X-ray Luminosity
16
38
40
42
44
46
48
41 42 43 44 45 46 47 48
y = -4.1059 + 1.0389x R= 0.78609
log
F E (e
rgs
s-1)
log L(20-100 keV) (ergs s-1)
Almost linear correlation between jet power and X-ray luminosity
FE ∝ LX1.04
Jet power ~ 0.5% of X-ray luminosity – with large deviations from mean
Somewhat misleading since alternative regression =>
LX ∝ FE0.6
Friday, 27 July 12
COSPAR 2012
Main points on disk-dominated X-ray AGN
17
• Need to understand better the relationship between radio and X-ray emission in both radio-loud and radio quiet sources where the X-ray emission is clearly disk coronal emission
• Important to focus on jet power rather than radio luminosity when considering the partition of gravitational power among various modes
• Consideration of the large scale source structure and dynamics useful way of estimating jet power
Friday, 27 July 12
COSPAR 2012
X-ray jet emission in the Radio-Loud Galaxy Centaurus A
18
Extended synchrotronemission
SED of core from Lenain et al ’09
Friday, 27 July 12
COSPAR 2012
Interaction of jet with ISM
192
Radio and X-ray Images from Hardcastle et al 2003 and 2007
Approaching side
Receding side
Friday, 27 July 12
COSPAR 2012
Interaction of jet with ISM
192
Radio and X-ray Images from Hardcastle et al 2003 and 2007
Approaching side
Receding side
Friday, 27 July 12
COSPAR 2012
Interaction of jet with ISM
192
Radio knot SW of nucleus
Radio and X-ray Images from Hardcastle et al 2003 and 2007
Approaching side
Receding side
Friday, 27 July 12
COSPAR 2012
Velocity of [SiVI] – 0.12” SINFONI – VLT
204
Corrected for rotation:
Neumayer et al. 2007
Friday, 27 July 12
COSPAR 2012
Why is [SiVI] blue-shifted?
215
Redshifted emission on approaching side and blueshifted on receding side at first counterintuitive
Expect entrained clouds to be moving with jet
Knot SJ1
Friday, 27 July 12
COSPAR 2012
Geometry
226
z
x
yJet
Counter –Jet
obs
cl
Cloud
Observervcl
x’(W)
y’(N)
SJ1
z-y plane definedby jet and observer
Friday, 27 July 12
COSPAR 2012
Shock models (MAPPINGS)
23
-0.5 0.0 0.5 1.0
-3.0
-2.0
-1.0
0.0
Blue Cloud
Total
precursor
shock + precursor
shock + precursor
shock only
shock only ß=10
ß = 0.1ß = 1ß = 10
1000 km/s
170 km/s
220 km/s
750
1000
1000 ß=11000
ß=10
1000 ß=0.1
750
500
350km/s
Log[ SiVI/Bra ]
Log[
CaV
III/B
ra ]
Friday, 27 July 12
COSPAR 2012
High energy emission from the core
248
Synchrotron + Inverse Compton model fits to the high energy emission from the core of Cen A – Lenain et al. 2009
Model Lorentz factor = 15Inclination ~ 25o
Estimates from VLBIobservations (Tingay et al. 01)
Lorentz factor > 1.12Inclination between450 and 80o
Extended synchrotronemission
Friday, 27 July 12
COSPAR 2012
Parameters of photoionization models
259
U =
No. density of ionising photons
Atomic no. density
=
nph
n↵ = Spectral slope of flux density
Flux density F⌫ / ⌫�↵
Typically ↵ ⇡ 1.4
and log U ⇡ �2
Lenain et al. models of X-ray synchrotron => ↵ ⇡ 0.39
Friday, 27 July 12
COSPAR 2012
Flux of ionizing photons
26
z
x
yJet
Counter –Jet
obs
cl
Cloud
Observervcl
x’(W)
y’(N)
SJ1
�obs
=
1
�(1� � cos ✓obs
)
�cl
=
1
�(1� � cos ✓cl
)
Doppler factors:
Lorentz factor
Friday, 27 July 12
COSPAR 2012
Ionizing flux (cont.)
2712
Nph
=Z 1
⌫0
Nph
(⌫) d⌫
=1c
✓DA
Dcl
◆2
✓�cl
�obs
◆3
Z 1
�obs
��1
cl
⌫0
Fobs
(⌫obs
)h⌫
obs
d⌫obs
z
x
yJet
Counter –Jet
obs
cl
Cloud
Observervcl
x’(W)
y’(N)
SJ1
DA
Dcl
=
Distance to Cen A
Distance of cloud from core
=
sin(✓obs
+ ✓cl
)
cl
Projected angular distance ofcloud from core
Friday, 27 July 12
COSPAR 2012
Results of photoionization calculations
2813
-0.5 0.0 0.5 1.0
-3.0
-2.0
-1.0
0.0
Log[ SiVI/Bra ]
Log[
CaV
III/B
ra ]
Blue Cloud
Total
Log U = -2.0
Log U = -1.0
Log U = +0.0
_ = +0.0
_ = -1.0
-0.8-0.6-0.4
-0.2
Optimal MAPPINGSmodel very close to the slope derived from high energy models
and .....
quite different from standard AGN models
log U = -1.9 typical of dusty photoionization models (Dopita et al. 2002)
Friday, 27 July 12
COSPAR 2012
Density and filling factor
29
Typical filling factors for entire NarrowLine Region in AGN ~ few x 10-2 – 10-4
Indicates modest Lorentz factors < 5
Friday, 27 July 12
COSPAR 2012
Conclusions for Centaurus A
30
• Blue-shifted cloud in the core of Centaurus A photoionized by high energy emission from base of jet
• But ... beamed emission from jet consistent with low Lorentz factor not 15 as claimed by high energy model
• Greater consistency with deductions from VLBI data
• Need for substantial revision of models for high energy emission
Friday, 27 July 12