the dust covering factor in agn: marko stalevski1,2,3

The dust covering factor in AGN:The dust covering factor in AGN:What's wrong and how to fix it

Marko Stalevski1,2,3

with

Claudio Ricci4,5, Yoshihiro Ueda5, Paulina Lira1, Jacopo Fritz6, Maarten Baes3

1 Universidad de Chile, Santiago, Chile2 Astronomical Observatory, Belgrade, Serbia

3 Sterrenkundig Observatorium, Universiteit Gent, Belgium4 Pontificia Universidad Catolica de Chile, Santiago, Chile

5 Kyoto University, Kyoto, Japan 6 Centro de Radioastronomıa y Astrofısica, UNAM, Morelia, Mexico

The dust covering factor in AGN:The dust covering factor in AGN:What's wrong and how to fix it

Ltorus/LAGN = CF

(e.g. Fritz+06; Hatziminaoglou+09; Mor+09; Mor & Trakhtenbrot11; Alonso-Herrero+11; Ramos-Almeida+11; Mor & Netzer12; Mateos+15,

16). (S. Mateos talk)

IR SED fitting → CF

(e.g. Maiolino+07, Treister+08, Calderone+12, Lusso+13, Netzer+16)

ΔΔ

Δ –Δ – opening angle opening angle

ΔΔ

Covering Factor ≈ sinΔ

Wada 2012 Stalevski+16

f*LAGN

(1-f)*LAGN = Ltorus

f*LAGN

(1-f)*LAGN = Ltorus

f*LAGN

Covering Factor = sinΔ ≈ Ltorus/LAGN

(1-f)*LAGN = Ltorus

f*LAGN

Covering Factor = sinΔ ≈ Ltorus/LAGN

Ltorus/LAGN = sinΔ · DA · TA

f (cosθ, Δ )f (τ,p,q,R,RadTrans,... )

Monte Carlo Radiative Transferhttp://www.skirt.ugent.be/

Baes+11; Baes & Camps 15; Camps & Baes 15

L ~ cosθ(1+2cosθ)

Anisotropic accretion disk:

Optical depth map (V-band) of the AGN sky

The two-phase torus model: high-density

clumps + low-density interclump

dust.

Density map of the xz plane.

Stalevski+12, 16

Stalevski+12, 16

Monte Carlo Radiative Transferhttp://www.skirt.ugent.be/

https://sites.google.com/site/skirtorus/

face-on view edge-on view

Ltorus/LAGN vs. CF: dust optical depth

Ltorus/LAGN vs. CF: disk-torus misalignment

Consequence forobscured AGN fraction vs. luminosity

IR vs X-ray CF discrepancy ?

XR

Ueda+14

Hasinger08

(e.g. Ueda+03; Hasinger08, Beckmann+09; Burlon+11; Ricci+13; Merloni+14; Ueda+14; Buchner+15;...)


IR

XR

Stalevski+16 Netzer+16

Ueda+14

Hasinger08


– Sazonov+15:

– negative bias in finding obscured AGN in hard X-ray flux limited survey

– positive bias in finding unobscured AGN, due to Compton reflection in the torus

→ lead to smaller obscured AGN fraction in the high-L than at low-L

– Anisotropic central XR source

Some questions and suggestions

– Lawrence 1991: Receding torus

– Lawrence & Elvis 2010: No receding torus (“In mid-IR samples, low frequency radio samples and local volume limited samples no evidence for an f_obsc luminosity dependence”)

– IR: torus seems not to be receding (Calderone+12, Roseboom+13, Netzer+16, Stalevski+16, Mateos+15: weak or no dependence of f_obsc on L_AGN)

– XR: torus seems to be receding... BUT WHY?(e.g. Ueda+03; Hasinger08, Beckmann+09; Burlon+11; Ricci+13; Merloni+14; Ueda+14; Buchner+15;...)

– gas torus + dusty torus: decoupled, different dynamics, different CFs ?

– Goodbye for the receding torus ?

ConclusionsConclusions

● Conspiracy of accretion disk and obscuring dust anisotropy messes up Ltorus/LAGN as dust CF proxy

● Type 1s: Low CFs underestimated; high CFs overestimated● Type 2s: CFs always underestimated

● New method to correct the observed Ltorus/LAGN

● Weak or no trend of obscured AGN fraction with luminosity! (f_obsc≈0.65)

● Goodbye receding torus?

Stalevski+2016 MNRAS 458, 2288–2302

https://sites.google.com/site/skirtorus/

[email protected]

the dust covering factor in agn: marko stalevski1,2,3

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