Chandra Observations of Relativistic AGN Jets
Dan Schwartz Smithsonian Astrophysical Observatory
TEXAS AT STANFORD 2004 December 15 Observations of Extragalactic X-ray Jets 3C 273 BC: 3 Clear Detections Cen A: Feigelson et al. 10" = 29kpc Chandra Launched: Jets start rollingM87: in.Biretta et al. CE: 3 Fields of Investigation • Interactions with gas in Seyferts, radio galaxies, clusters.
• FR I and BL Lac jets. • Quasars, Powerful Radio Sources, and Cosmology. Observations of Extragalactic X-ray Jets BC: 3 Clear Detections Chandra Launched: Jets start rolling in. WHY? Angular Resolution!
3C 273
10" = 27 kpc
3C 273
0.5 to 7 keV 10" = 27 kpc
10" = 29kpc 3C 273
0.5 to 7 keV INTRODUCTION
•WhatDoJetsDo? – Carry large quantities of energy, to feed radio lobes – Significant part of black hole energy generation budget – Interact with gas in galaxies and clusters of galaxies INTRODUCTION
•WhatDoJetsDo? – Carry large quantities of energy, to feed radio lobes – Significant part of black hole energy generation budget – Interact with gas in galaxies and clusters of galaxies •WhatDoWeWanttoLearn –Particlecomposition and acceleration – Jet acceleration and collimation INTRODUCTION
•WhatDoJetsDo? – Carry large quantities of energy, to feed radio lobes – Significant part of black hole energy generation budget – Interact with gas in galaxies and clusters of galaxies •WhatDoWeWanttoLearn –Particlecomposition and acceleration – Jet acceleration and collimation • Why Do We Need X-Ray Data? – Spectral Energy Distribution (SED) gives mechanism – Particle lifetimes change with observed band PKS 0637-752
z=0.653 0.5-7 keV X-rays
8.6 GHz
K1 K2 K3 K4
11"=76 kpc PKS 0637-752
z=0.653 0.5-7 keV X-rays
8.6 GHz
K1 K2 K3 K4
11"=76 kpc Spectral Energy Distribution often indicates against Synchrotron X-rays
PKS 1030-357
Quasar 12" = 109 kpc
K 1
Quasar K 3
K 3 K 1 K 2 K 2
5" = 43 kpc
Quasar
10" = 72 kpc K 1
Knot 2
Knot 1
5" = 40.3 kpc K 2 Quasar Spectral Energy Distribution often indicates against Synchrotron X-rays
AB
A B
A B A B
Sambruna et al., 2002ApJ...571..206S Spectral Energy Distribution often indicates against Synchrotron X-rays
Inverse Compton X- rays from the CMB:
2−3 γx ≈10 4−5 γr ≈10
Some jets may be de- tectable by GLAST, at 10−13 to 10−12 ergs cm−2 s−1
Sambruna et al., 2002ApJ...571..206S PKS 0637-752 Jet Spectrum 600
400
200
0 0510 110 Confront IC/CMB with Morphology
1000
100
10
1 024681012 Confront IC/CMB with Morphology Naive Models 1000
100
10
1 024681012 Confront IC/CMB with Morphology Naive Models
Siemiginowska et al. 2002 ApJ...570..543S PKS 1127-145 at z=1.187
PKS 1421-490 Images Gelbord et al. a) b) c)
A1 B A2
C N
5’’ E
0 ATCA 20 GHz Magellan i Chandra 0.5–7keV PKS 1421-490 Spectra Gelbord et al.
Core Model Jet Model Radio–Optical: Synchrotron Radio–Optical: Synchrotron Equipartition Equipartition B=13mG, Γ=20, θ=2.9◦ B=85mG 20≤ γ ≤ 104 104 ≤ γ ≤ 2 × 106 3 γbreak = 10 X-ray: Upstream Comptonization? X-ray: SSC • Determined B and δ within a factor of 2 • Kinetic flux is ∝ (Bδ)2, for equipartition 20
15
10
5
5 1015202530 Kinetic Flux 20 •K=Γ2π r2β cU • U is total internal energy
15 density, UB+Ue+Up • For equipartition, 2 10 B U= 8π (2 + k) • NOTE: K constant ⇒ 2 5 (B Γ) = constant
5 1015202530 Kinetic Flux 20 •K=Γ2π r2β cU • U is total internal energy
15 density, UB+Ue+Up • For equipartition, 2 10 B U= 8π (2 + k) • NOTE: K constant ⇒ 2 5 (B Γ) = constant •WetakeΓ ≈ δ = Γ − −1 5 1015202530δ ( (1 β cos(θ))) − •cos(θ ) = √δ 1/δ max (δ2−1) Kinetic Flux 10 From K =Γ2π r2β cU,
∝ 2 2 2 K δ θr(3 B /(8 π))
1
0.1 100 1000 Kinetic Flux From K =Γ2π r2β cU,
∝ 2 2 2 K δ θr(3 B /(8 π))
Kinetic flux is a signif- icant, even dominant, portion of the accretion energy budget. Implications of the AGN Jets • Eddington Luminosity might not limit Accretion Rate
• Jets may Power Cluster Cavities – Stop Cooling Flows
• IC/CMB X-ray jets Maintain Constant Surface Brightness vs. z. We will detect them at Arbitrarily Large Redshift. 100
10
0.1 1 10 100
10
0.1 1 10 100
10
0.1 1 10 100
10
0.1 1 10 Where ARE the bright X-ray Jets at High Redshift? • Unidentified ROSAT sources? • Bright ROSAT, ASCA, EINSTEIN quasar identifications? • Extreme X-ray/Optical sources (Koekemoer et al. 2004ApJ...600L.123K) in Chandra Deep Surveys? Where ARE the bright X-ray Jets at High Redshift?
3" = 20kpc
GB 1508+5714 z=4.3
Siemiginowska et al. 2003ApJ...598L..15S Cheung,2004ApJ...600L..23C Two more High Redshift X-ray Jets: Cheung et al. Poster 1613
2 arcsec ~ 14 kpc
Quasar 1745+624 = 4C +62.29 at z=3.889
PMN J2219-2719 at z=3.634 There Could Be Radio Quiet X-Ray Jets!
• 1 keV X-rays produced by γ ≈ 1000/Γ • ν =4.2×10−6γ2 H[µG] ≈ 10 MHz
1000 0246810 There Could Be Radio Quiet X-Ray Jets!
• 1 keV X-rays produced by γ ≈ 1000/Γ • ν =4.2×10−6γ2 H[µG] ≈ 10 MHz
109 GB 1508+5714
108 (Jy Hz) ν F ν 107
6 z=4.3 10 1000 0246810 108 1010 1012 1014 1016 1018 Frequency (Hz) Cheung,2004ApJ...600L..23C A Radio Quiet X-Ray Jet?
EMSS 0841+1314 z=1.8661
30" 13 11 20 15 13 11 30 10
05 DECLINATION (J2000) 00
10 55
08 41 29.0 28.5 28.0 27.5 RIGHT ASCENSION (J2000) 15 J0841
00 DECLINATION (J2000)
10 45 30" = 273 kpc f8.6GHz ≤ 100µJy Correlation of X-ray Jet and Radio Flux Densities Significance of the X-ray Emission
1. X-rays dominate power radiated by jet 2. SED through X-ray band provides clues to structure. • Acceleration sites • Deceleration of bulk motion • Proton content Significance of the X-ray Emission If emission is inverse Compton on the Cosmic Microwave Background 3. X-rays give the effective Doppler factor, rest frame B, and electron γmin 4. X-ray jets will be detectable at arbitrarily large redshift!