The Large Scale Structure of Seyferts and LINERs and Implications for their Central Engines

The The Large Scale StructureLarge Scale Structure of of Seyferts and LINERsSeyferts and LINERs

and and Implications for their Implications for their Central Central

EnginesEngines

Anca Constantin

Drexel University

AGN are not unbiased tracers of the whole galaxy population, with respect to mass:

- Seyferts are less clustered than galaxies less massive but actively accreting BHs

- LINERs cluster like galaxies. more massive but weakly active BHs

--with thanks to Michael Vogeley

The SDSS main galaxy sample -DR2

• 2627 sq. deg. footprint area • ~250,000 galaxies with spectra • 0 < z <~ 0.3• rdered < 17.77

• Broad-line objects (spectroscopically flagged as QSOs) excluded

The SDSS main galaxy sample -DR2

• 2627 sq. deg. footprint area • ~250,000 galaxies with spectra • 0 < z <~ 0.3• rdered < 17.77

• Broad-line objects (spectroscopically flagged as QSOs) excluded

“ Best” absolute magnitude limited sample

Finding AGN among SDSS galaxies

Seyferts

H II

nuclei

LINERs

Transition objects

emission-line

20% of all galaxies are strong line-emitters

among which: 52% H II20% (pure) LINERs7% Transition Objects

5% Seyferts

The Clustering Amplitude r0:

H IIs: r0= 5.7 0.2 less clustered than galaxies

Seyferts: r0= 6.0 0.6

less clustered than galaxies

LINERs: r0= 7.3 0.6 clustered like galaxies

r0 is measured in h-1 Mpc = scale where the probability of finding a galaxy pair is 2 random

all galaxies: r0= 7.8

0.5 Absolute Magnitude limited samples,

-21.6 <M < -20.2

The Clustering Amplitude r0:

H IIs: r0= 5.7 0.2 less clustered than galaxies

Seyferts: r0= 6.0 0.6

less clustered than galaxies

LINERs: r0= 7.3 0.6 clustered like galaxies

r0 is measured in h-1 Mpc = scale where the probability of finding a galaxy pair is 2 random

all galaxies: r0= 7.8

0.5

higher peaks in the density field are more clustered

Seyferts & H II’s: - less massive Dark Matter halos

LINERs: - more massive Dark Matter halos

Absolute Magnitude limited samples, -21.6 <M < -20.2

The Clustering Amplitude r0:

H IIs: r0= 5.7 0.2 less clustered than galaxies

Seyferts: r0= 6.0 0.6

less clustered than galaxies

LINERs: r0= 7.3 0.6 clustered like galaxies

r0 is measured in h-1 Mpc = scale where the probability of finding a galaxy pair is 2 random

all galaxies: r0= 7.8

0.5

higher peaks in the density field are more clustered

Seyferts & H II’s: - less massive Dark Matter halos

LINERs: - more massive Dark Matter halos

Absolute Magnitude limited samples, -21.6 <M < -20.2

MBH Seyferts < MBHLINERs

MDM halo ~ MBH

(Ferraresse 2002, Baes et al. 2003)

Driven by the host morphology?

H IIs Seyferts LINERsblue red-ish red-ish, KScolor = 0.617

late type earlier types like Seyferts! KSconc = 0.104

blue red

earlylate

Driven by the host morphology? NO!

H IIs Seyferts LINERsblue red-ish red-ish, KScolor = 0.617

late type earlier types like Seyferts! KSconc = 0.104

blue red

earlylate

Low L[O I]: r0= 13.15

1.09LINER dominated

High L[O I]: r0= 6.1 0.3

H II dominated

Low L[O III]: r0= 8.8 0.7

LINER dominated

High L[O III]: r0= 6.2 0.6

almost no LINERs!mostly H II

high L[O I]

high L[O III]

low L[O I]

low L[O III]

lowest L[O I],[O III] objects = strongly clusteredhighest L[O I],[O III] objects = weakly clustered

Different availability of fuel?

LINERs show particularly low levels of obscuration

& gas densities

Seyferts exhibit generally

high gas densities& moderately high NHI

Summary & Possible interpretation

H IIs Seyferts LINERs

hosts: blue red-ish red-ish, late type earlier types like the Seyferts

r0: weakly weakly clustered like

clustered clustered average galaxies

fueling average relatively high (very) low rate: -efficient? -inefficient?

gas low high lower thandensity: in Seyferts

obscuration: high wide range (very) lowBH mass: small small large

life-time: ? short long

Constantin & Vogeley 2006, in ApJ today

Stellar massBH mass

Accretion rate, [O I] Accretion rate, [O III]

Stellar ages Obscuration

Dist to 3rd nearest Dist to 1st nearest