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P.Coppi, Yale

AGN à la Blandford , cont. [ What Worked, What Didn’t, and What Next? ]. ?. P.Coppi, Yale. What’s a Blandford, à la Google:. Kid’s definition. Dr. Roger Blandford Astrophysicist

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P.Coppi, Yale

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  1. AGN à la Blandford, cont. [ What Worked, What Didn’t, and What Next? ] ? P.Coppi, Yale

  2. What’s a Blandford, à la Google:

  3. Kid’s definition Dr. Roger Blandford Astrophysicist His research interests include: black holes, those famous supermassive space objects that gobble up matter and light; "gravitational lensing," which refers to the way light travels in curved paths around stars and galaxies; high-energy waves from space known as gamma ray bursts; the dim class of stars known as white dwarfs; and the structure and evolution of the universe. [pbs.org]

  4. AGN à la Blandford, ca. 1986, IAUS

  5. EGRET GeV Blazars… Mkn 421 TeV Blazars… Fossati et al. 2002 Mkn 421 Gaidos et al. 1996 One of the biggest surprises! Pian et al. 1998

  6. PKS 2155, ~5 min variability

  7. Another superluminal jet source …oops … it’s in our galaxy!

  8. A “boring” object in the sky: the nearby elliptical galaxy M87 Radio Optical “FEAST vs. FAMINE” A starved black hole…..

  9. X-ray variability seen in HST-1 knot too!! M87 jet is not wimpy!!! D. Harris,2003

  10. ADIOS: The X-ray/Radio correlation … GX339 - Corbel et al. 2004 AGN !? - Maccarone et al. 2003

  11. Another major development: arcsecond X-ray Imaging CDF-N/GOODS 2Msec(!) Chandra CDF-S When you can see with X-rays, again black holes much more common!

  12. Guess what: our black hole is not special!Every big galaxy has one ! The “M-s Relation” (Ferrarese & Merritt, see also Gebhardt et al.)

  13. Finally some answers? Rare long-lived AGN vs. many short-lived AGN? Seems to be tilting decisively towards FEEDBACK??? Even “low energy” astronomers can’t ignore black holes…

  14. Blandford was right…. While LCDM appears correct, Both galaxy and AGN formation do seem to be anti-hiearchical (kind of) … At z=2, massive elliptical progenitors COMPACT and this one may have σ ~500 km/sec!!

  15. The “Feasting Objects” (FSRQ): interesting probes? Eagerly await Fermi results on n(z), but in meantime have SWIFT/BAT survey: see Ajello et al. 2009 ….

  16. Old (pre-CGRO) view of gamma-ray Universe.

  17. My model for the pre-CGRO sources… The transitionfrom a non-thermal to a thermal pair plasma… Coppi 1998

  18. After CGRO… Johnson et al., 1994 …. There goes the thesis….

  19. EGRET Blazars and gamma-spheres:

  20. Even though pairs may not be dominant, that pair plasma code was good for something …. Compilation by A. Zdziarski

  21. Spectra of this quality generally do not exist for AGN! Chandra ?? Possible AGN spectral “states” not well-sampled!

  22. What if you don’t have broad band data – X-ray binary example… What’s E_cut => no idea what reflection spectrum to expect !

  23. No broad band data = big uncertainties! PEXRIV kTe = 85 keV,R = 1.0, t= 1.3 (green) Ecut =900 kev, R=0.5, x=100 kTe = 68 keV,R = 0.4, t= 1.8 Your line fit is only as good as your continuum fit/model! RXTE PCA OSSE Ecut =100 kev, R=1, x=0 BAT Fitting only <20 keV or >50 keV leaves big uncertainty in predictions for other half of spectrum. Even with great statistics, an X-ray mission that only measured spectrum 20-150 keV allows a factor two uncertainty in reflection fraction!

  24. Spectra of this quality generally do not exist for AGN! Chandra ?? Possible AGN spectral “states” not well-sampled!

  25. In fact, we are just starting to see tip of iceberg in terms of possible AGN spectra! Red dots - measured values Black dots – lower limits Contrary to what is assumedin XRB model fits, there is a large scatterin high energyspectra of AGN (both in power law indexandhigh-energy cutoff). ~30% of objects have E_C > 400 keV, which is NOT obviously compatible with XRB shape … ? Typical (single) value assumedfor XRB models… [N.B. The objects shown are a large fraction of the existing sample of AGN withgood HX spectra! ] Risaliti et al. 2002, BeppoSAX survey of Compton-thin Seyfert 2’s (NH~ 1022 – 1024 ) …

  26. Our view of the black hole universe is still highly biased….

  27. The Super-Antennae, IRAS 19254 (Braito et al., 2009, Suzaku)

  28. Even if the unabsorbed spectrum did not vary (unlikely), we know the environment varies. Details like the exact geometry of the absorber matter, especially in the Compton thick (NH > 1024) case, and may depend on host type, redshift, etc. This complication is largely ignored in current XRB models – we need broadband measurements of many objects to disentangle intrinsic vs. extrinsic (absorber-induced) variations! Sample theoretical calculation (Monte Carlo, exact) -- Lines of sight Geometry of obscuring material – a sphere. with an empty conical hole, and possible paths of photons. Spectrum on axis (black), perpendicular to axis (green), and on edge of obscuring material (red), and spectrum of source (dashed), for an opening of 30% of surface area, NH=1.0E25 and EC=300 KeV.

  29. Different obscuration geometries imply different polarization signatures. X-ray/gamma-ray polarimetry difficult but very useful! Disentangles geometry and emission components. Degree of polarization perpendicular to axis (green) and on edge of obscuring material (red) – same parameters as above.

  30. On cosmic train wrecks, feasting, and the formation of black holes… How do we make quasars at z>6!?

  31. Don’t ignore that gas! Escala et al. 2004 Multi-scale simulation by Mayer et al. 2009

  32. LISA: gravitational waves! Sensitivity best for LOWER mass (MBH<106 Mo) mergers!

  33. Escala 2008 Origin of M-sigma relation? Fueling-limited scenario! ENZO AMR simulation including star formation and accretion onto “large” central black holeparticle -- who needs a seed black hole?

  34. Radio Where are the black holes?? 1 arc sec ? Keck Adaptive Optics 2.2 micron X-Ray NGC 6240 Max et al. 2007, Science

  35. [Sorry  ]

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