1. Radio Galaxies in X-Ray Light: Problems and Processes Dave De Young NOAO Radio Galaxies in the Chandra Era 8-11 July 2008

2. Major Unresolved Issues – Radio Galaxies in the Pre-Chandra era Origins of Energetic Particles – How and Where Formation of Bipolar Outflows Collimation Mechanisms Outflow Speeds Outflow Content Total Energies Outflow Lifetimes

3. Major “Resolved” Issues – Radio Galaxies in the Pre-Chandra era Morphology/Radio Luminosity Classification – FR-I and FR-II Radio Radiation - Incoherent Synchrotron Must Have Relativistic Electrons and Magnetic Fields “Superluminal Features” on Small Scales

4. Some Major Revelations from Chandra Extended X-Ray Emission From Jets, Hot Spots, and Lobes

5. Revelations from Chandra – Large Scale X-Ray Jets Revelations from Chandra – Large Scale X-Ray Jets Electron Synchrotron Lifetimes in Equipartition Fields: – X-Ray: Decades to Centuries – Optical and UV: Millennia Therefore High Energy Electrons Cannot Have Been Energized Only in Nucleus Immediate Impact on Models

6. Revelations from Chandra – Low Power (FR I) X-Ray Jets Electron Synchrotron Models Can Work Single SED Can Fit Radio to X-Ray Requires Local Acceleration in Knots Can Produce Offsets Simultaneous Variations at X-ray to Radio Problems/Uncertainties: Distributed Acceleration – Two Populations? Occasional Wrong SED No Radiative Cooling Signatures?

7. Revelations from Chandra – Hot Spots and Lobes X-Ray Emission Consistent with SSC and IC/CMB Under Equipartition Conditions First “Verification” of Equipartition Assumption Kataoka & Stawartz 2005, Croston et al. 2005

8. Revelations from Chandra – Large Scale (QSO, FR II, Blazar) X-Ray Jets Revelations from Chandra – Large Scale (QSO, FR II, Blazar) X-Ray Jets Schwartz et al. 2000 Sambruna et al. 2004

9. Large Scale X-Ray Jets Harris & Krawczynski 2006 Siemiginowska et al. 2007, 2008

10. Large Scale X-Ray Jets The IC/CMB Model – Tavecchio et al. 2000, Celotti et al. 2001 PKS 0637-752: Γ ~ 10 Reproduces SED Has Three Basic Assumptions – Equipartition Conditions – Relativistic Motion on 10-100 Kpc Scales – Population of Low Energy electrons Schwartz et al. 2000

11. Large Scale X-Ray Jets Electron Kataoka & Stawartz 2005

12. Large Scale X-Ray Jets – The IC/CMB Model Some Issues – Low Energy γ ~ 10-100: Long Electron Lifetimes Why X-Ray Knots? – Required Beaming Angles Imply Jet Lengths ~ 1 Mpc or More, >> FR II Jets – Equipartition + Low Energy End of Spectrum May Imply “Too Much” Energy – Bulk Speeds at 100s kpc >> Other Derived Values

13. IC/CMB Issues Kataoka et al. 2008 3C 33 Kraft et al. 2007

14. Revelations from Chandra – Large Scale X-Ray Jets Revelations from Chandra – Large Scale X-Ray Jets Reacceleration for Electron Synchrotron – First Insights into Energy Injection Question – Stringent Requirements on Shock Models – Can Account for Most Low Power FR-I Jets Possibility of IC/CMB for FR-II/Quasar Jets – Requires Relativistic Bulk Motion at 100s kpc First Possible Clues to Jet Speeds on Large Scales – Implies Low Energy Electron Population First Possible Constraints on γ(min)

15. Other Radio Galaxy Results from Chandra Other Radio Galaxy Results from Chandra Radio Galaxy Interactions with the Environment E.g., Cen A (Kraft et al. 2007)

16. More Major Revelations from Chandra Radio Galaxy Inflated Cavities in Clusters NGC 1285/Perseus Fabian et al. 2000

17. Radio Source Cavities N1275 Fabian et al. 2000

18. Radio Source Cavities in Clusters Chandra A2052 + 6cm VLA (3C 317) Blanton et al. 2001, Burns 1990

19. Properties of Radio Source Cavities and Shells Morphology – Limb Brightened, “Relaxed” Structure – NOT Head-Tail or “Normal” FR-I – Small/No Jets, but t ~ 10 yr – Tens of kpc in Diameter Inferred Properties – In Pressure Equilibrium – Generally Moving Subsonically – Shell and Surroundings Cool – Buoyant Bubbles 7 syn

20. Relic Sources in Clusters N1275 74 MHz Fabian et al. 2002

21. Properties of Radio Relics They Are Intact! At Times >> t Reside 30-50 kpc From Cluster Center Diameter 10-20 kpc Buoyant Risetimes ~ 10 yr > Synchrotron Lifetime Equilibrium Implies U >> U PdV Work ~ 10 erg (or More) intequip 59 instab 8

22. Calorimetry of Radio Galaxy Outflows After > 35 Years of Assumptions and Guessing McNamara & Nulsen 2007

23. Calorimetry of Radio Sources in Clusters MS 0735 – Z = 0.22 pdV ~ 10 erg! 62 McNamara et al. 2005, 2007

24. Stability of Relic Sources in Clusters t >> t buoyR-T, K-H vs

25. The “Cooling Flow” Problem and Heating Due to Radio Sources Sound Waves? Shock Waves? Fabian et al. 2005  P/P

26. What Have We Learned and What Remains Unsolved? Origins of Energetic Particles – In Situ Acceleration Required in Addition to Nuclear Processes Formation of Bipolar Outflows – ? See Finis Collimation Mechanisms – ? See Finis Outflow Speeds – May Be Relativistic on Mpc Scales Outflow Content – Coupled to Speed Question? Total Energies – Enormous Progress: Firm Limits Outflow Lifetimes – See Item 4

27. A Possible Path to Further Progress – Jet Interactions With Their Environment Key Issue: The Coupling of AGN Outflow to the Surrounding Medium – Ambient Medium with Known Properties – Determination of Dominant Physical Processes at Work – Constrain Basic Parameters of Outflow

28. AGN Outflows FRII 3C98 3C223 – 20cm

29. AGN Outflows FRI

30. AGN Outflows FRI

31. AGN Outflows

32. – Surface Brightness

33. Outflow Interaction with Ambient Medium Fully Non-Linear K-H Instability: – Development of Turbulent Mixing Layer

34. Mixing Layers Thickness Grows with Distance/Time Mixing Layer Can Permeate Entire Jet   - RELHL )(v)/( CTan 

35. Mixing Layers Entrainment Very Effective – “Ingest – Digest” Process

36. Mixing Layers K-H and Mixing Layers in Supersonic Flows Relativistic Flows – 3D Simulations Rigidity Deceleration Development of Shear/Mixing Layers Aloy et al.; Marti et al. 1999-2003

37. The Effect of Magnetic Fields Can Stabilize – In Principle Three Dimensional MHD – For High Beta > 100 Evolves to Turbulence Turbulent B Amplification Enhanced Dissipation due to Magnetic Reconnection – Instability Remains “Essentially Hydrodynamic” Ryu et al. 2000

38. Mixing Layers MHD Plus Relativistic Mizuno et al. 2007

39. Outflow Interaction Via Surface Instabilities Virtually Universal (One Possible Exception) – Present at Some Level in Outflows in All Environments Global – Involve Most of Jet Surface for Long Times Inevitable (?) – Very Special Circumstances Required to Prevent Occurrence

40. Consequences of Mixing Layers Saturated Mixed Jets - and FR I Source Morphology

41. Consequences of Mixing Layers Entrainment Deceleration Spine/Sheath Structure Decollimation How Much of Each? – TanΘ ~ (ρ /ρ ) / M 3C223 – 20cm 12 

42. Consequences of Mixing Layers: IC/CMB Models Can Γ ~ 10 to ~ Mpc be Sustained? Other Measures of Γ: v Structure Is U >> U ? Implications for Content What is “Too Much” Energy? pB

43. Consequences of Mixing Layers: IC/CMB Models – Other Issues Evidence for Sustained Energy Transport Where are “Debeamed” Jets? Probable Need for Jet Models With Complex Internal Velocity Structure Hardcastle 2006

44. Another Possibility Poynting Flux Jets – Origins Well Defined – Initial Collimation Solved – Development of Mixing Layer – Not Clear – Long Term Collimation? – Particle Content? Li et al. 2006

45. Evolution of Turbulent Flows Development of the Turbulent Cascade

46. Issues for This Week Issues for This Week The FRI / FRII Dichotomy (and IC/CMB Jets) – Difference in Degree or Kind? – Nature vs. Nurture – Jet Content – Jet Speed Collimation – Difficult with External Pressure ( ~ d ) – Difficult with Magnetic Fields 

47. Issues for This Week Poynting Flux Jets – Are There Unique Observational Signatures? Radio Sources in Clusters – Cooling Flows, Feedback etc. – Consequences for General Radio Sources Total Energies Energy Fluxes Outflow Speeds Jet Content