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Unification Issues and the AGN TORUS

Unification Issues and the AGN TORUS. Moshe Elitzur University of Kentucky. Unification prediction #1. type 2 = type 1 + obscuration namely every type 1 class has a corresponding type 2 QSO2 MUST exist!

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Unification Issues and the AGN TORUS

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  1. Unification Issues and the AGN TORUS Moshe Elitzur University of Kentucky

  2. Unification prediction #1 type 2 = type 1 + obscuration namely every type 1 class has a corresponding type 2 QSO2 MUSTexist! QSO2 DO exist, even with hidden type 1 engines at z = 0.6 (Zakamska et al 05)

  3. Prediction #2 — SED: 2 = 1 - AGN MRK1239 Rodrìguez-Ardila & Mazzalay ‘06

  4. VLTI — NGC1068: IR Puzzle #1 Jaffe et al ‘04 r  1.7 pc: T = 320 K T > 800 K Poncelet et al ‘06 Lbol = 2·1045 erg s-1(Mason et al ’06) T(r = 2pc) = 960 K r(T = 320 K) = 26 pc r(T = 226 K) = 57 pc

  5. Temperature in Clumpy Medium Tmax Tmin Nenkova et al 2006

  6. IR Puzzle #2 While its obscuration is highly anisotropic, the torus emission is nearly isotropic: Lutz et al ’04 — 6µm vs 2-10 keV x-rays Horst et al ’06 — 12µm vs 2-10 keV x-rays Buchanan et al ’06 — 5-35µm vs radio R = IR/radio

  7. Clumpy Torus – Radial Density Variation 0 N  N0exp(-2/2)/rq N0 = 5 = 45º V = 60 Large q (steep radial decline) — Anisotropic obscuration with nearly isotropic emission!

  8. Clumpy Torus Modeling • N0 = 5 – 10 clouds •  = 30° – 60° • V= 40 – 120 • q = 1 – 2 • Rs = 0.9L½12 pc; Ro > 5 Rs s N  N0 exp(-2/2)/rq Standard ISM dust works fine Nenkova et al ‘02; ‘06

  9. Unification Statistics 0 f2 — fraction of obscured sources = N2/(N1 + N2) Seyferts: f2 = 70% Schmitt et al 01 f2 = 50% Hao et al 05 f2 decreases with luminosity (Simpson 05, Hao et al) — “receding torus” (Lawrence 91) f2 = sin  = 0.5 — 0.7 H/R = tan ~ 0.7 — 1 H Rs R Basic Premise AGN type determined uniquely by viewing angle

  10. Clumpy Unification 0 Nc() = N0 exp(-2/2) AGN type is a viewing-dependent probability! • Type 1 sources from “type 2 viewing”, and vice versa • Flips between type 1 & 2 (Aretxaga et al 99) • f2 variations may arise from either  or N0or both f2 depends on both  and N0!

  11. Unification and X-rays • Evidence for types 1 & 2 orientation-dependence in both X-ray absorption and reprocessing • Absorption-corrected type 2 spectra & luminosities are similar to type 1 (Smith & Done 96; Turner et al 97) BUT: The “X-ray torus” probably does not coincide with the “dusty torus”

  12. Dusty vs X-rays Torus • NH(X-ray) ~ 3 — 100 NH(UV) (Maiolino et al 01) • From IR modeling NH(torus) <~ 1024 cm-2, yet at least ~50% of Seyfert 2 are Compton thick (Guainazzi et al 05) • Fast X-ray variations — absorbing clouds are dust-free Risaliti, Elvis & Nicastro 02 Rs RX

  13. RX Rs Dusty vs X-rays Torus (2) • X-ray observations + IR observations and modeling: NH(X-ray) ~ 10 NH(torus) • If Nclouds ~ 1/r2 then RX ~ Rs/10 (and Rs ~ 0.9 L121/2 pc) f2(X-rays) may be quite different from f2(UV/optical)! Sarah Gallagher (Tuesday): Compton thick “x-ray only” absorption in QSO1 (x-ray and UV not consistent with each other)

  14. 0 Torus Size • NGC1068: 2m imaging – R ~ 1 pc (Weigelt et al 04) 10m interferometry – R ~ 2 pc (Jaffe et al 04) • Cen A: 2m – R < 0.5 pc (Prieto et al 04) 9 & 18m – R < 2 pc (Radomski et al 06) • Circinus: 2m – R ~ 1pc (Prieto et al 04) 8 & 18m – R < 2 pc (Packham et al 05) • NGC1097 & NGC5506: 2m – R < 5 pc (Prieto et al 04) All observations are consistent with Rout/Rs no larger than ~20-30, and perhaps even only ~5-10

  15. Dynamic Origin of Vertical Structure Cloud accretion from the galaxy? No need in a compact torus!

  16. 0 The Torus as a Disk-Wind Region Everett & Konigl 00 Bottorff et al 97

  17. Cloud Properties in Torus Outflow v ~ 20 – 150  NH ~ 1022 – 1023 cm-2 Resistance to tidal shearing: n > 107M●7 /rpc3 cm-3 Rc < 1016 NH,23 rpc3 /M●7 cm Mc < 7·10-3 NH,23 Rc,162 Mo B ~ 1.5 1km/s n71/2 mG Elitzur & Shlosman 2006

  18. 0 Unification Scheme

  19. masers BLR TORUS Broad Lines Region BAL Broad Absorption Lines Toroidal Obscuration Required by Unified Schemes 0 Grand Unification Scheme Emmering, Blandford & Shlosman 92

  20. Outflow and Accretion Torus disappears at L <~ 1042 erg s-1 !

  21. Torus Disappearance at Low Luminosities • Nucleus visible at L <~ 1042 erg s-1 radio galaxies (Chiaberge et al 99) and LINERs (Maoz et al 05) • No torus dust emission in M87 (Whysong & Antonucci 04; Perlman et al 06) and NGC 1097 (Masson et al 06)

  22. If only TORUS is removed, all low-luminosity AGN become type 1 HOWEVER • Both type 1 and type 2 LINERs do exist (Maoz et al 05) • “true” type 2 AGN exist at L < 1042 erg s-1 (Laor 03) THEREFORE BLR must disappear at some lower L

  23. Torus BLR • Wind diminishes — mass outflow directed to jets (?) • Ho (2002): Radio loudness varies inversely with Macc! • Similar effect in x-ray binaries .

  24. High Low Full Unification Scheme; both type 1 & 2 Accretion Rate Radio Loudness molecular outflow extinguished Torus disappears; type 1 only atomic outflow extinguished BLR disappears; “true” type 2 High Low

  25. Issues for Study • It’s all probabilities! • X-ray vs UV/optical TORUS properties • f2 decrease at high L — NH or ? • TORUS disappearance at low L — NH or v? • Low-luminosity end of AGN: • IR emission • Switch from outflow to jets

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