Connections between Radio and High Energy Emission in AGN

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Magnus Lawson
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1 Connections between Radio and High Energy Emission in AGN Geoff Bicknell Research School of Astronomy & Astrophysics Australian National University 1

2 Collaborators: Loredana Bassani, INAF, Bologna Nadine Neumayer, ESO, Munchen Francesca Panessa, INAF, Roma Ralph Sutherland, RSAA Andrea Tarchi, INAF, Cagliari Alex Wagner, Tsukuba University 2

3 Motivation: * Partition of Black Hole Gravitational Power into: 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 3

4 Origin of X-ray emission Radio loud: Predominantly flat spectral index Two main possible emission mechanisms: Radio quiet: Predominantly steep spectral index Comptonization of soft disk photons by hot corona Synchrotron or Inverse Compton emission from jet Shastri et al. 93 4

5 Black Hole Fundamental Plane Merloni & Heinz 03 Falcke 04 5 GHZ core luminosity vs 2-10 kev luminosity Offset in Galactic and Extragalactic correlations due to black hole mass log L R =1.05 log L X log M

6 Panessa et al 2007 Seyfert galaxies (radio quiet) Low luminosity Radio Galaxies Difference of 3 orders of magnitude in radio luminosity but same slope L X / L 0.97 R 6

7 Panessa et al Correlation lost at VLBI resolution VLA core VLBI core Suggests correlation with jet power rather than luminosity 7

8 INTEGRAL Sample INTEGRAL 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.) kev 8

9 Different modes of X-ray and radio emission Gamma-ray and/or X-ray emission region Wind Shock or reconnection region Jet Corona Ordered magnetic field Chaotic magnetic field Disk and corona dissipate gravitational power rapidly Jet Poynting flux-dominated, non dissipative Jet power manifest on kpc scales 9

10 Relationship between radio power and jet power 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

11 NGC 4051: Giroletti & Panessa 09 ~ 19 kpc bubble on large scales fed by jet on small scales 11

$Powerful 10 45 ergs s -1 jet in 1 kpc fractal$

12 Jet Interstellar Medium interaction Density Powerful ergs s -1 jet in 1 kpc fractal medium 12

13 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 13

14 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 13

15 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 K estimated from electron pressure K 3p tot pe m e c 2 p tot (a 2) 1 13

16 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 K estimated from electron pressure K 3p tot pe m e c 2 p tot (a 2) 1 Lower cutoff 13

17 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 K estimated from electron pressure K 3p tot pe m e c 2 Radius and pressure of bubble R = At 3/5 p tot = 12 A = 25 aa 2 t 4/5 apple F E p tot 1/5 a (a 2) 1 Lower cutoff 13

18 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 K estimated from electron pressure K 3p tot pe m e c 2 Radius and pressure of bubble R = At 3/5 p tot = 12 A = 25 aa 2 t 4/5 apple F E p tot 1/5 a (a 2) 1 Ambient density Lower cutoff 13

19 Luminosity of bubble Emissivity j = Numerical Factors KB (a+1)/2 N( ) = K a (a 1)/2 K estimated from electron pressure K 3p tot pe m e c 2 Radius and pressure of bubble R = At 3/5 p tot = 12 A = 25 aa 2 t 4/5 apple F E p tot 1/5 a (a 2) 1 Ambient density Jet energy flux Lower cutoff 13

20 Luminosity - Jet Power relation P = j Volume B = Equipartition with total pressure 14

21 Luminosity - Jet Power relation P = j Volume B = Equipartition with total pressure P Numerical Factor 3(a+1)/20 a F (a+11)/10 t (4 a)/5 (3 a)/2 E 14

22 Luminosity - Jet Power relation P = j Volume B = Equipartition with total pressure P Numerical Factor 3(a+1)/20 a F (a+11)/10 t (4 a)/5 (3 a)/2 E n a 1 cm 3 14

23 Luminosity - Jet Power relation P = j Volume B = Equipartition with total pressure P Numerical Factor 3(a+1)/20 a F (a+11)/10 t (4 a)/5 (3 a)/2 E n a 1 cm 3 t yr 14

24 Luminosity - Jet Power relation P = j Volume B = Equipartition with total pressure INTEGRAL sample: =1.4 GHz P Numerical Factor 3(a+1)/20 a F (a+11)/10 t (4 a)/5 (3 a)/2 E n a 1 cm 3 t yr 14

25 Radio power -> Luminosity Strongest dependence is on energy flux P / F (a+11)/10 E ) F E / P 10/(a+11) = P 0.76 for a =2.2 15

26 Energy flux X-ray Luminosity log F E (ergs s -1 ) 48 y = x R= log L( kev) (ergs s -1 ) Almost linear correlation between jet power and X-ray luminosity FE LX 1.04 Somewhat misleading since alternative regression => LX FE 0.6 Jet power ~ 0.5% of X-ray luminosity with large deviations from mean 16

27 Main points on disk-dominated X-ray AGN 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 17

28 X-ray jet emission in the Radio-Loud Galaxy Centaurus A Extended synchrotron emission SED of core from Lenain et al 09 18

29 Interaction of jet with ISM Radio and X-ray Images from Hardcastle et al 2003 and 2007 Approaching side Receding side 192

30 Interaction of jet with ISM Radio and X-ray Images from Hardcastle et al 2003 and 2007 Approaching side Receding side 192

31 Interaction of jet with ISM Radio and X-ray Images from Hardcastle et al 2003 and 2007 Approaching side Receding side Radio knot SW of nucleus 192

32 Velocity of [SiVI] 0.12 SINFONI VLT Neumayer et al Corrected for rotation: 204

33 Why is [SiVI] blue-shifted? Knot SJ1 Redshifted emission on approaching side and blueshifted on receding side at first counterintuitive Expect entrained clouds to be moving with jet 215

34 Geometry y y (N) Jet z-y plane defined by jet and observer x obs x (W) SJ1 cl v cl Observer z Counter Jet Cloud 226

35 Shock models (MAPPINGS) 1000 km/s 0.0 Total shock + precursor ß = 10 ß = 1 ß = Log[ CaVIII/Brγ ] shock only ß= km/s Blue Cloud 1000 ß= ß= ß=1-3.0 shock + precursor shock only precursor 170 km/s 350km/s Log[ SiVI/Brγ ] 23

36 High energy emission from the core Synchrotron + Inverse Compton model fits to the high energy emission from the core of Cen A Lenain et al Extended synchrotron emission Model Lorentz factor = 15 Inclination ~ 25 o Estimates from VLBI observations (Tingay et al. 01) Lorentz factor > 1.12 Inclination between 45 0 and 80 o 248

37 Parameters of photoionization models U = No. density of ionising photons Atomic no. density = Spectral slope of flux density Flux density F / = n ph n Typically 1.4 and log U 2 Lenain et al. models of X-ray synchrotron =>

38 Flux of ionizing photons Lorentz factor y y (N) Jet Doppler factors: obs = cl = 1 (1 cos obs ) 1 (1 cos cl ) Counter Jet SJ1 Cloud cl v cl obs Observer x z x (W) 26

39 Ionizing flux (cont.) Z 1 N ph = N ph ( ) d = 1 c 0 DA D cl 2 cl obs 3 Z 1 obs F obs( obs) 1 cl h 0 obs d obs D A Distance to Cen A = D cl Distance of cloud from core = sin( obs + cl ) cl y y (N) obs Jet x x (W) Projected angular distance of cloud from core Counter Jet SJ1 Cloud cl v cl Observer z 27 12

40 Results of photoionization calculations 0.0 Log U = -1.0 Total Optimal MAPPINGS model very close to the slope derived from high energy models Log U = +0.0 Log[ CaVIII/Brγ ] Log U = -2.0 Blue Cloud and... quite different from standard AGN models α = -1.0 α = Log[ SiVI/Brγ ] log U = -1.9 typical of dusty photoionization models (Dopita et al. 2002) 28 13

41 Density and filling factor Indicates modest Lorentz factors < 5 29

42 Density and filling factor Typical filling factors for entire Narrow Line Region in AGN ~ few x Indicates modest Lorentz factors < 5 29

43 Conclusions for Centaurus A 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 30

Osservatorio Astronomico di Bologna, 27 Ottobre 2011

Osservatorio Astronomico di Bologna, 27 Ottobre 2011 BASIC PARADIGM: Copious energy output from AGN (10 9-10 13 L Θ ) from accretion of material onto a Supermassive Black Hole SMBH ( 10 6-10 9 M Θ ). AGN