The AGN Obscuring Torus

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The AGN Obscuring Torus
Moshe Elitzur University of Kentucky
LAOG, Grenoble
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Happy Birthday, young man!
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optical depth
zone
tz tt
z
tz-1
ti
?ij ?i ?j
i
?i,i-1 Ti Ci pi ? ni1 ni2
ti-1
t2
2
t1
1
Coupled Escape Probability
t0 0
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2-level Atom
? 10-3
Slab ?t 500
Semi-infinite Atmosphere (10-3 ? ? ? 107)
Time Time error, S error, S
zones ALI CEP ALI CEP
1 0.03 ? 99.5 55.5
20 1.02 ? 88.2 23.0
40 3.29 ? 79.8 15.5
100 12.6 .033 62.5 6.5
200 28.1 .085 46.4 2.2
Time Time error error
zones ALI CEP ALI CEP
20 0.39 ? 36.3 104
40 1.10 ? 23.9 45.7
100 4.39 0.06 10.9 14.0
200 11.6 0.89 5.5 5.4
600 44.9 1.70 1.6 1.2
Elitzur Asensio Ramos 2006, MNRAS 365, 779
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Unified Scheme for AGN
Toroidal Obscuration Required by Unification Schem
es
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Torus Properties
0

• From the statistics of type 1 vs type 2 H/R 1
  (Schmitt et al 01)
• R ? Must rely on IR emission

General folklore R ? 100 pc
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Origin of the 100s pc Torus Modeling IR
emission
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• Dearth of IR emission in smooth-density models
  T ? r

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Observations NGC 1068, CO
Schinnerer et al 00
at R 70 pc, H 9 10 pc ? H/R 0.15
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Observations NGC 1068, CO H2
20 pc
140 pc
Galliano et al 03 H/R 0.15
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IR Observations
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• 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 lt 0.5 pc (Prieto et al 04)
  9 10?m R 1.5 pc (Karovska et al
  03)
• Circinus 2?m R 1pc (Prieto et al 04)
  8 18?m R lt 2 pc (Packham et al 05)
• NGC1097 NGC5506 2?m R lt 5 pc (Prieto et al
  04)

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The Torus Size Crisis

• Observations compact (pc-size) torus
• Theory extended (100s pc) torus

Lbol 21045 erg s-1 (Mason et al 06) T(r
2pc) 960 K r(T 320 K) 26 pc r(T 226
K) 57 pc
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Temperature in Clumpy Medium
Tmax
Tmin
Nenkova et al 2006
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TemperatureDistance Relation
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• Smooth density T R uniquely related
• Clumpy density different T at same R
  different R, same T

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AGN Clumpy Torus Size Effect
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Ri 0.9 pc L½12 Y Ro/Ri
N ? N0r -q exp(-?2/?2)
N0 5 ? 45º ?V 60
Clumping solves the compact emission problem!
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Dynamic Origin of Vertical Structure
Cloud accretion from the galaxy? No need in a
compact torus!
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The Torus as a Disk-Wind Region
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Bottorff et al 97
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Unification Scheme
0
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Grand Unification Scheme
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Emmering, Blandford Shlosman 92
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Cloud Properties in Torus-Wind
Size shear resistance
Density
Mass
Magnetic field
Elitzur Shlosman 2006
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Water Masers Glimpse of Torus Clouds?
NGC 3079
Kondratko, Greenhill Moran 05
High-latitude features disk rotational imprint
uplifted clouds
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Outflow and Accretion
Torus disappearance at L ? 1043 erg s-1 !
Narrow-line Seyfert 1 radio galaxies? Chiaberge
et al 99 Whysong Antonucci 04
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Conclusions

• No bagel
• Toroidal Obscuration Required by Unified Scheme
  just a region in the disk-wind