1 / 25

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!

shona
Télécharger la présentation

Unification Issues and the AGN TORUS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  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

More Related