Upload
amal-conway
View
34
Download
1
Tags:
Embed Size (px)
DESCRIPTION
[OIV]25.89. [NeII]12.81. PAH11.3. PAH12.7. PAH7.7/8.6. PAH6.2. Silicate Emission in Active Galaxies. Mario Schweitzer. MPE. E. Sturm, D. Lutz, R. Genzel, S. Veilleux, D. Rupke, D.-C. Kim, B. Groves, D. Tomono, Hagai Netzer. - PowerPoint PPT Presentation
Citation preview
Silicate Emission in Active Galaxies
Mario Schweitzer
MPE
E. Sturm, D. Lutz, R. Genzel, S. Veilleux, D. Rupke, D.-C. Kim, B. Groves,
D. Tomono, Hagai Netzer
QUESTQuasar And ULIRG Evolution Study
Emission From The Torus Or (And) Extended Emission ???
[OIV]25.89
[NeII]12.81
PAH7.7/8.6
PAH6.2
PAH11.3PAH12.7
10m Silicate emission in Type 1 AGNOriginal prediction of torus models, but not really observed until very recently…
Suggested modifications to explain absence of silicate emission:- changes of grain size distribution (Laor & Draine 1993, Maiolino et al. 2001)- Special geometries, e.g. tapered disks (Efstathiou & Rowan-Robinson 1995)- Clumpy tori (Nenkova et al. 2002)
Opt. thin dust, different size distributions (Laor & Draine 93)
Type 1 SED for different radial distributions of clumps (Nenkova et al. 02)
0.1 1 10m 100 1000
q : power law exponent for radial clump distribution
ß: power law exponent of size distribution
Siebenmorgen et al. 2005 Hao et al. 2005
Spitzer finally finds silicate emission in luminous AGNs (PG QSOs)
Siebenmorgen et al. 2005
Hao et al. 2005
Conditions in the silicate emitting region
Weingartner & Draine 2001
The Unification model
sublimation temperature between 800 and 1500 K(Kimura et al. 2002)
But estimated temperatures are ~ 200 K too cold
Silicate emission in Type 2 objects!
NGC 4725: Type 2 AGN from Ho sample (SINGS data, Kennicutt et al.)
QSO2s: Sturm et al. 2006
IRASF10214+4724: Teplitz et al. 2006
Silicate emission – the Torus?
possibly spatially extended silicate emission
cold temperatures + silicate emission in type 2
Model the silicate emission
…and at lower luminosity A testcase for the spatial extension of
the silicate emission regionNGC 3998 (Liner 1.9) Sturm et al. 2005
L (2-10 keV) = 3 x 10 ^41 ergs/s (Ptak et al. 2004)
T~180K(from feature ratio and ISM silicate emissivity profile).
Follow-up SUBARU (COMICS) observation of NGC3998A preliminary result
I11.7
-I8.6
2MASS JHK-band (NED)
image size : 200 pc2
(together with DaigoTomono)
fluxd
en
sity
[Jy
]
C8.6
I
=
First image of extended (residual) silicate emission in AGN
~35pc
this is a upper limit since no PSF-correction !
D ~ 35 pc
image size : 200 pc2
Using illuminated cloud models from Brent Groves (MPA):
D ~ 30 pc
Conclusions- Silicate emission detected in AGNs over four orders of magnitude in
luminosity. Origin in torus or extended emission ?
- Arguments for extended emission:
1) Estimated temperatures (optical thin) are much lower then the sublimation temperature !
2) Silicate emission has been detected also in type 2 AGNs.
3) For the LINER NGC 3998 we find silicateemission on a scale of D ~ 30 pc (preliminary result)
In addition to more Spitzer spectroscopy, these issues call for very high resolution observations and interferometry!
res. : 0.1´´ (~7 pc)wavelength: 12.5 µm
NGC 1068: ~2/3 of emission extended (overlapping the NLR)and likely isotropic
(Cameron et al. 1993, Bock et al. 1998, 2000, Tomono et al. 2001)
12.5 µm
Details not well fit by standard astronomical silicate
Sturm et al. 2005
peak shift:- temperature- grain sizes- crystallization- composition
used synthetic ISM-extinction curve from Weingartner and Draine (2001)
2e3 erg s-1cm-2
2e5 erg s-1cm-2
Fitting of NGC3998:
Rdust: ~200 L460.5pc
L46~ 4.84e-3
(estimated by scaling Lbol of PG0050+124 by ratio of x-ray (2-10keV) luminosities)
Rdust ~ 14 pc D ~ 30 pc
Using illuminated cloud models: Brent Groves (MPA)
Hotter component also needed
From Imaging : D ~ 35 pc
Jacquelin Kessler-Silacci et al.
wavelength [µm]
180 K
1100 K
ISM extinction curveby Weingartner and Draine (2001)
The QUEST-projectEvolution of Activity in Massive Gas-Rich Mergers
-study basic physical processesinvolved in
-creating massive early type hosts -growing/feeding of massive BH
in galaxy mergers
50% of cosmic star formation at high zand most of the big BH´s appear to beformed in this process
understand this process better in the local univers apply knowledgeto high z.
-Test the Sanders-scenario
…
M ~ 107 – 1010 M
~1pc
~100 pc – few kpc
Rout < 100 pc
Rout < 35 pc : NGC 1068 (Keck 8-25 µm Bock et al 00) NGC 4151 (Gemini 10 & 18 µm Radomski et al 03)
Follow-up SUBARU (COMICS) observation of NGC3998A preliminary result
I11.7
-I8.6
1.88 x
6.87.11
)(6.11
7.11
)(6.8
6.8
6.8
7.116.87.11 88.1 II
Fs
Fc
c
cIII
total
total
fluxd
en
sity
[Jy
]
S11.7
c11.7
C8.6
I
2MASS JHK-band (NED)
image size : 200 pc2
(together with DaigoTomono)
Similar Galactic SEDs:
flared, passive irradiated protostellar disks
Dullemond et al. 2001, 2004
… but of course cannot be scaled simply!