Thaisa Storchi Bergmann Instituto de Física, UFRGS, Porto Alegre, RS, Brazil
The LLAMA Project Evaluation Workshop, FAPESP, São Paulo, August 8-9, 2011
Rogemar A. Riffel Peter McGregor Fausto Barbosa Claudia Winge Allan Schnorr Muller David Sanmartin Guilherme Couto Rodrigo Nemmen Tiberio Borges Vale
¡ AGN (Active Galactic Nuclei) structure ¡ HST images: AGN feeding ¡ Gemini NIFS data ¡ Nuclear source: dusty/molecular torus ¡ Gas kinematics: inflows ¡ Need for ALMA/LLAMA data
Supported by broad lines seen in polarized (scattered) light in NGC1068: Antonucci & Miller 1985, Antonucci 1993; other Seyfert 2: Tran, Kay (1990’s, early 2000’s)
Dusty/molecular torus: inner portion of feeding flow to the Supermassive Black Hole Size (dust sublimation radius): 0.01 – 1 pc -> 0.15 – 15 mas for ~15 Mpc (Virgo) Accretion disk: 0.05 mas Event horizon: ~10-4 mas (MW ~ 0.1 mas)
Elitzur 2007; Nenkova 2008: toroidal, clumpy obscuration region 1-10 pc; Maybe stars in it (Wada 2009, fig. from Zier & Bierman 2002)
Fig. by Schartmann et al. 2008
Netzer & Laor 1993: BLR outer boundary set by dust sublimation Rd; Rd: inner boundary of the torus; Both BLR and torus originating from an accretion disk wind (Elitzur & Ho 2009; Risaliti & Elvis 2010)
Fig. from Gaskell et al. 2007
Simões-‐Lopes et al. 2007:
§ Structure maps: HST F606W early-‐type AGN vs. non-‐AGN
§ Dusty nuclear spirals in ~100% AGN;
§ But in ~ 25% of non-‐AGN;
èChannels to feed the SMBH ?
AGN Non-AGN AGN Non-AGN
Optical: GMOS § FOV: 3.5”x5” or 5”x7” § Sampling 0.2” , Res. 0.6” § R~3000
Near-‐IR: NIFS +ALTAIR Superb instrument! ¡ FOV: 3” x 3” ¡ Sampling: 0.04”×0.1” ¡ Res. 0.1” ¡ R~5500, Z, J, H & K-‐band
§ GMOS IFU: 3 fields 5”x7”=15”x7”(1.2x0.6 kpc) § Measured gas kinematics (Hα +[NII]) § Fit and subtract a circular rotating disk model § Look for residuals in association with nuclear spirals
§ Fit and subtraction of circular rotation model to the velocity field;
§ Residuals of up to 50 km/s along nuclear spirals;
§ Mass inflow rate of ionized gas: ~10-3 Msun yr-1
§ Davies et al. 2009: flow in warm molecular gas (Davies et al. 2009) § Another case: NGC6951 (Storchi-Bergmann et al. 2007)
§ In many cases kinematics is too disturbed to fit circular model
§ GMOS IFU: 3 fields 5”x7”=15”x7”(255x120 pc2)
§ Measured stellar and gas kinematics (Hα +[NII])
§ Subtract stellar from gaseous kinematics
§ Look for residuals in association with nuclear spirals
Gas kinematics Stellar kinematics
§ Stellar kinematics: major axis along y; rotation axis along x;
§ Gas kinematics distinct: “rotation axis” perpendicular to stellar
§ Relation between velocity, velocity dispersion and structure map: shocks in the plane;
§ If gas is in the plane, blueshifts in the far side èinflows
PC3: rotating disk being fed along minor axis
PC4: bi-polar outflow related to radio jet (arrow)
PC5: more of the disk
§ 3”x 4”(135x180pc)
§ 0.1”= 4.5 pc
§ Unresolved K-band source
§ Torus R≤2.3 pc
H2 channel maps
§ Nuclear spiral arms within inner ~ 50 pc down to inner 2.3 pc; blueshifts in far side, redshifts in near side. If gas is in the plane è inflow
§ Mass inflow rate ~1/100 mass accretion rate è only “hot skin” of molecular gas flow § Cold molecular gas: ≥ 105 larger (Dale et al. 2005) è Mass inflow rate ≥1 Msun yr-1
§ 0.1”= 6.5 pc
§ [FeII]: along ionization cone; 100 pc
§ H2: “toroidal” flux distribution; 50 pc § Coronal lines: barely resolved
Within 4 pc from nucleus: black body with temperature T=1340K è dusty torus
§ 0.1”= 6.5 pc § Unresolved nuclear K-
band source § Torus R≤3.3 pc
Channel maps: distinct kinematics between ionized and molecular gas: § [Fe II]: (a) highest velocities along axis of ionization cone; (b) correlation with radio at zero velocities; (c) outflows at 2 Msun yr-1
§ H2: low velocities: rotation in the plane
Riffel, R. A. & Storchi-‐Bergmann 2010):
§ 0.1”= 23.3 pc § 3”x3” (700x700 pc2)
§ Unresolved nuclear source
Spectral synthesis using STARLIGHT (Cid Fernandes): § Old population (109-10 yr) within 0.5” of nucleus);
§ Unresolved (within ~11 pc) black-body at the nucleus (~1000K)
§ Intermediate age (3-7 x 108 yr) stellar population at low-σ ring è such rings as signatures of post-starburst population
H2 channel maps: inflows in warm molecular gas
FAR
NEAR
HST Optical structure map
§ Centroid velocity map and σ map for H2(warm molecular gas): compact rotating disk (100 pc) with low low σ fed by spiral arms è
§ Model by Maciejewski (2009, with Davies): spiral arms as shocks in the gas driving inflows è
¡ Inflows along nuclear “tongue” in warm molecular gas (Mueller Sanchez et al. 2009);
¡ Other similar works on other objects by Richard Davies group at MPE
§ Inflows on scales of 10 -‐ 100 pc mapped in ionized (HII) and molecular gas;
§ Structure: nuclear spiral arms or nuclear disks;
§ Mass inflow rates: ~ 10-‐3 M¤ yr-‐1 in ionized gas and even smaller in warm molecular gas;
§ Total inflow rate larger, in cold molecular gas; Dale et al. (2005): cold/warm molecular gas ratio: 106è inflow rate ~ few M¤ yr-‐1
§ Martini et al. (2011): Spitzer dust masses of nuclear spirals ~ 105 M¤; Mgas ~ 107 M¤; if activity lasts 107 yr, inflow rate ~ 1 M¤ yr-‐1
§ Next step: flux distribution and kinematics in cold molecular gas: ALMA, LLAMA
NGC1097, Nobeyama MM Array, Kohno et al. 2003 § Strong HCN at the nucleus, but
beam 4.4”x 10”; cannot resolve distribution nor kinematics
§ Need ALMA/LLAMA observations to obtain actual inflow rate
§ How does it compare with the “extrapolated” ~1 M¤ yr-1?
NGC1365, Sub-mm Array (SMA), Hawaii, Sakamoto et al. 2007
NGC3227, PdBI, Sani et al. 2011, HCN at nucleus: higher density gas
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