Ionization patterns in the Ionization patterns in the circumstellar medium of active circumstellar medium of active

galaxiesgalaxies

Joss Bland-HawthornJoss Bland-Hawthorn

(AAO)(AAO)

Collaborator:Collaborator: P.R. Maloney (U Colorado) P.R. Maloney (U Colorado)

NGC 7742 Seyfert 2NGC 7742 Seyfert 2

How much could we learn from How much could we learn from millimag optical-IR photometry?millimag optical-IR photometry? SMEX mission: SMEX mission:

1.5m aperture, off-axis camera, 1.5m aperture, off-axis camera, differential photometer, space differential photometer, space environment, long-term programenvironment, long-term program

2001 TRACE Satellite 2001 TRACE Satellite observations of the observations of the solar limb...solar limb...

Optical-IR variability Optical-IR variability vsvs. `ionization cones’. `ionization cones’

Both involve two or more of:Both involve two or more of:

accretion disk activity accretion disk activity (intrinsic)(intrinsic)

circumnuclear properties circumnuclear properties (extrinsic)(extrinsic)

illumination geometry illumination geometry (extrinsic)(extrinsic)

beaming effects beaming effects (intrinsic)(intrinsic)

viewing angle viewing angle (extrinsic)(extrinsic)

Is observed phenomenon intrinsic to source or extrinsic?Is observed phenomenon intrinsic to source or extrinsic?

AGNs can have far-reaching influence within ISM...AGNs can have far-reaching influence within ISM...

(Begelman 1985)(Begelman 1985)

Even as late as 1987, astronomers were not ready to Even as late as 1987, astronomers were not ready to believe this.believe this.

The assumption was that The assumption was that (a)(a) most jets were orthogonal to most jets were orthogonal to the disk, the disk, (b)(b) the recently discovered dust tori would block the recently discovered dust tori would block UVX radiation from hitting the disk.UVX radiation from hitting the disk.

However, we now suspect that in low luminosity AGNs, the However, we now suspect that in low luminosity AGNs, the dust tori / accretion disks precess wildly. Frequently, the dust tori / accretion disks precess wildly. Frequently, the torus opening angle intersects the large-scale disk.torus opening angle intersects the large-scale disk.

MR 2251-178: the Largest Known Quasar Nebula

• One of the few radio-quiet quasars with a extended gaseous nebula

• Spiral complex extends more or less symmetrically over ~ 200 kpc

• M(nebula) < 6 x 1010 Msun (ionized)

• Photoionized by the quasar

• Smooth large-scale rotation, in opposite sense to the inner region of the galaxy

• Morphology and large-scale rotation seem to rule out origin from cooling flow, past merger event, or interaction with nearby galaxy G1

• Favor a model in which the extended ionized nebula resides within a large complex of HI gas centered on the quasar

(Shopbell, Veilleux, & JBH 1999)

H

Z = 0.0638

maximum vel. gradient

jet axis

Ionization Cones

• Arguably the best example of ionization bi-cone

• The line-emitting gas is very extended (~ 40 kpc) and consists of a complex network of filamentary strands

• Gas is photoionized by Seyfert 2 nucleus

• Complex kinematics are best explained as the superposition of two inclined rotating disks

• Origin: past galaxy merger event?

(Tadhunter & Tzvetanov 1989; Wilson & Tzvetanov 1994; Morse et al. 1998)

Contour: Green Continuum

Grey Scale: [O III] 5007

NGC 5252

Veilleux & JBH 1997; Wilson et al 2001Veilleux & JBH 1997; Wilson et al 2001

HST imaging of CircinusHST imaging of Circinus[OIII][OIII]

HH

NGC 7213

• Line-emitting filament is located ~ 18.6 kpc from Seyfert 1 nucleus

• Multi-line images and optical spectra show that the warm gas is not ionized by H II regions

• Warm gas is blueshifted by 100 – 150 km s-1 with respect to systemic

(Veilleux & Rupke 2001; Hameed et al. 2001)

H + [N II] 6583 + continuum

5 kpc

19 kpc

NGC 7213

• HI map reveals NGC 7213 to be a highly disturbed system suggesting a past merger event

• Line-emitting filament seems to coincide spatially and kinematically with HI filamentary structure (NH ~ 1 x 1020 cm-2 near filament)

(Hameed et al. 2001)

HI 21 cm vs. H + [N II]

4 kpc

NGC 1068

• Line-emitting filamentary complex detected out to ~ 12 kpc from the nucleus, slightly beyond the HI edge

(Shopbell, JBH & Veilleux 2001) log(H)

HI 21 cm (Brinks)

Digital Sky Survey

HST [O III]

(Macchetto et al. 1994)

20 kpc

20 kpc

10 kpc

Boundaries of Ionization Cone ?

NGC 1068

• Filamentary complex is seen in both H and [O III] 5007

• Likely source of ionization: AGN

• Likely origin: ambient material illuminated by AGN

(Shopbell, Bland-Hawthorn, & Veilleux 2001)

log(H) log( [O III])

10 kpc

N

Young, Wilson, Shopbell 2001Young, Wilson, Shopbell 2001

Chandra observationsChandra observations

X-ray ionization cone in NGC 1068X-ray ionization cone in NGC 1068

NGC 1068 multi-band diagnosticsNGC 1068 multi-band diagnostics

11um11um

Other effects are dust or electron scattering out of Other effects are dust or electron scattering out of

the beam the beam (( < 0.1) < 0.1) - see Sokolowski, JBH & Cecil 1991- see Sokolowski, JBH & Cecil 1991ee

MAPPINGS MAPPINGS (Sutherland & Dopita)(Sutherland & Dopita)

Energy range: Energy range: 1 eV to 12 keV1 eV to 12 keV

Predict w.r.t. H-betaPredict w.r.t. H-beta

[NII][NII]

[SII][SII]

[OI] [OII] [OIII][OI] [OII] [OIII]

HeIIHeII

[NeIII] [NeV][NeIII] [NeV]

[Fe VII] [Fe X][Fe VII] [Fe X]

Log ULog U00 22

Isotropic illumination through a solid torusIsotropic illumination through a solid torus

Log [OIII]/HLog [OIII]/H

Line ratios wrt HLine ratios wrt H

R < 50 kpcR < 50 kpc

Log [OIII]/[OI]Log [OIII]/[OI]

00 77

Isotropic illumination through soft-edge torusIsotropic illumination through soft-edge torus

R > 50 kpcR > 50 kpc grey opacitygrey opacity

11-1-1

Log [OIII]/HLog [OIII]/H

Isotropic illumination through torus with opaque edgesIsotropic illumination through torus with opaque edges

R > 50 kpcR > 50 kpc

Cf. to grey cones, we Cf. to grey cones, we get the reverse effect get the reverse effect at the edges. The at the edges. The ionization goes up.ionization goes up.

Beamed illumination (intrinsic)Beamed illumination (intrinsic)

Log [NeV]/[NeIII]Log [NeV]/[NeIII]

-1-1 66

R < 1 kpcR < 1 kpc R < 50 kpcR < 50 kpc

00 22

Log [OIII]/HLog [OIII]/H

Asymmetric illumination out to 10 kpcAsymmetric illumination out to 10 kpc

Log [OII]/[OIII]Log [OII]/[OIII]

-2-2 00

Concluding remarksConcluding remarks

• Accretion disks and starburst winds both influence ISM over scales of 10 kpc or more, either radiatively or through powerful winds

• The ionization pattern in the circumnuclear ISM can provide important clues about the nature of the source or surrounding medium (a key area for IFUs, TFs on 8-10m class telescopes)

• Should we be considering differential optical/IR photometry of AGNs to an accuracy of < 1 millimag?

New class of New class of

edge-on ionizededge-on ionized

cones, e.g. cones, e.g. CenACenA

Find TTF imageFind TTF image

Also, N4945 Also, N4945 with powerful with powerful Lx and diffuse Lx and diffuse gas. Does this gas. Does this have cone?have cone?

But accretion disks are not the only But accretion disks are not the only phenomena to produce ionization cones...phenomena to produce ionization cones...But accretion disks are not the only But accretion disks are not the only

phenomenon to produce ionization cones...phenomenon to produce ionization cones...

M 82

11 kpc

H + [N II] HIFI

H + [N II] HST

(Shopbell & JBH 1998; Shopbell et al. 2001)

Devine & Bally 1999Devine & Bally 1999

There are instances where powerful There are instances where powerful wind and illumination by accretion disk wind and illumination by accretion disk are both operating...are both operating...

NGC 3079: Starburst-Driven Superbubble

(Veilleux et al. 1994; Cecil, JBH, Veilleux & Filippenko 2001)

Red = H Blue = [N II] 6583 Green = continuum Resolution: 0.1” 8 pc

1 kpc

Energetics: p(outflow) ~ (1–3) x 1047 f½ dyn s-1; KE(outflow) ~ (0.2-2.5) x 1055 f½ ergs where f > 0.003; LW (mech) ~ 1043 ergs s-1

HST

Large-Scale Outflow in NGC 3079 ?

The dwarf S0 galaxy NGC 3073 exhibits an elongated HI tail remarkably aligned with the nucleus of NGC 3079

Ram pressure due to outflowing gas may be responsible for tail

If so: Routflow 50 kpc

NGC 3079

NGC 3073

(Irwin et al. 1987; Filippenko & Sargent 1992; Cecil et al. 2001)

20 kpc

1 kpc

N

Radio Axis

20 cm

HI tail

Galactic wind

(Strickland & Stevens 2000)

log (density)

Disk Disk

Starburst

Free wind

Shocked haloShell fragments

Shocked wind

Summary Recent technological developments have allowed the study of

the warm ionized medium in the local universe down to unprecedented flux levels

Observations at these faint flux levels have detected ionized material on the outskirts of normal and active galaxies• Gas expelled from the galaxies by local and large-scale outflows

• Ambient gas ionized by active nuclei and starbursts

This material can be used to constrain • The warm-gas cross-sections of nearby galaxies

• The impact of star formation and nuclear activity in disk galaxies and their environments (e.g., metal abundance, heating, …)

• The distribution, intensity and spectrum of the ionizing radiation escaping from the cores of starburst and active galaxies

Future (now!):• Broad- & narrow-band shuffle mode: doubles efficiency

• Nod & shuffle mode: virtually eliminates systematic errors associated with sky line variations pure Poisson noise integrate as long as needed!

Emission-Line Morphology of Normal Isolated Edge-On Spirals

Thick ionized disks and/or filamentary structures are detected out to 1 – 5 kpc from the planes of the galaxies in the sample

Both the mass and extent of the extraplanar material in these galaxies appear to be correlated with the (local) surface density of star formation activity

(Miller & Veilleux 2001)

NGC 2188 NGC 2820 NGC 3044 NGC 4013

H Images

Heating vs. ionization

• Sokolowski 91

• Reynolds Haffner & Tufte 99

4/18.2426.04 2.12 TeT

H

NII

TTee (10 (1044 K) K)

NII/HNII/H

Multi-Line Imaging of Normal Edge-On Spirals

The observed emission-line ratios of the high-|z| ionized gas in spiral galaxies differs considerably from those of HII regions

Heating/ionization ratio increases with increasing vertical heights

Sources of ionization: • “Filtered” diluted OB

radiation from disk

• Shocks

• Turbulent mixing layers(Miller & Veilleux 2001)

H 6563 [N II] 6583 [N II]/H

NGC 891