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Active galaxies / Active galactic nuclei (AGN)

Active galaxies / Active galactic nuclei (AGN). Central engine variability put limit on size: R ≤ c  var Schwarzschild radius: R s = 2 G M / c 2 R s = size approx Uranus orbit for 10 9 M  Accretion allows conversion of 0.1mc 2 (fusion only 0.7%)

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Active galaxies / Active galactic nuclei (AGN)

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  1. Active galaxies / Active galactic nuclei (AGN) Central engine variability put limit on size: R ≤ c var Schwarzschild radius: Rs = 2 G M / c2 Rs = size approx Uranus orbit for 109 M Accretion allows conversion of 0.1mc2 (fusion only 0.7%) Radiation pressure will larger than gravity if L > LEDD Accretion disk very hot continuum source => X-rays Broad line region, dense ionised clouds, rapid moving Narrow line region, dilute ionised clouds, slower reverbration mapping Obscuring torus with dust and molecular gas, sublimation evacuate central part -> torus Relativistic (superluminal) Jets, and radio Lobes

  2. Unified AGN models Idea: all AGN are basically the same phenomena Differing due to different viewing angle and scale: Face on view: see all components: Sy1, QSO if looking into jet: Bl Lac (Blazar) Edge on view: see only hot torus and NLR, Sy2 Why some radio loud while others not? Unified BH model not perfect, but nothing else works

  3. Unified Model

  4. Spiral seyfert2 with radio jets Seyfert1

  5. QSO evolution - where are they now? Debate if fall off at z>3 is real There must be many dead QSOs around in the local universe!

  6. Kinematical evidence for BH in M87 + Grav redshifted X-ray em-lines detected in Sy1’s

  7. Relation between black hole mass and sigma of host galaxy: a realtion between BH and Spheroid Mass -- Black Hole doesn’t care about disk -- Co-evolves with spheroid/bulge!

  8. Clusters And Large Scale Structure (chapt. 4)

  9. M33 LeoI Sex A

  10. Tidal drag on NGC205 from M31

  11. Local Group

  12. HCG31 Galaxy Evolution/ Transformation Caught in action

  13. Rich clusters: Virgo and Comairregular vs regular (large spiral fraction) (mostly ”early” types)) (more relaxed)

  14. Hot gas in clustersX-ray emitting through thermal bremsstrahlung Efficient way of finding clusters

  15. Butcher-Oemler effect, etc: As we look back in time, the spiral fraction of Rich clusters become higher and higher (BO) Cluster and Galaxy transformation Interactions: galaxy mergers cluster merger galaxy harassment ram pressure stripping diffuse intracluster light: stars + gas vs Hot intracluster gas

  16. Masses of clusters: Virial theorem: M = RAv2 / G - does it apply? X-ray gas in Hydrostatic equilibrium - does it apply? Gravitational lensing: it does apply but only gives mass contrast - Methods agree fairly well (factor of 2)

  17. Gravitational lensing

  18. Einstein ring

  19. Abell 2218, strong lensingcf weak lensing (statistical)

  20. Angular distribution of Abell-clusters Brightest cluster galaxy method allows rough space distribution to be inferred

  21. Virgo supercluster Bound? -Not relaxed LargeScale Flows

  22. Sponge-like topology of universe CfA Redshift Survey Great wall Voids! Finger of god

  23. SDSS

  24. Intergalactic matter

  25. Gunn-Peterson effect

  26. Cosmic shear Challenging! - Effect on each individual galaxy tiny - Only visible through lareg and deep samples

  27. Measuring Clustering - Count in cells - 2-point corellation function

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