The local environment of low-z Seyfert and BIRG galaxies

V. Chavushyan

Koulouridis Elias

M. Plionis

Y. Krongold

D. Dultzin

C. Goudis INAOE

NOA

IA UNAM

“Local and Large Scale Environment of Seyfert Galaxies”

Complications for the Unification Model.

Koulouridis, E.; Plionis, M.; Chavushyan, V.; Dultzin, D.; Krongold, Y.; Goudis, C.

“Local and Large Scale Environment of Bright IRAS Galaxies”

The AGN/Starburst Connection.Koulouridis, E.; Chavushyan, V.; Plionis, M.; Krongold, Y.; Dultzin, D.

Unification Model(Antonucci 1993)

BLR NLRBLR NLR

ne≈1010cm-3 ne≈102-6cm-3

M~1-103M ⊙ M~1-106-9M⊙

Size ≈ 1pc Size ≈ 1kpc

Seyfert and Control Samples Dultzin-Hacyan et al., 1999

Samples of Seyfert were compiled from the catalog of Lipovetsky, Neizvestny and Neizvestnaya

48 Sy1 (0.007<z<0.036) 47 Sy1-control 56 Sy2 (0.004<z<0.020) 41 Sy2-control Same morphological type,

redshift, and diameter distributions.

Magnitude distribution of Sy1 peaks closer to CfA/SSRS limit.

Neighbours with mB≤15.5 (CfA2 & SSRS)

Red : Sy1 Blue : Sy2 Significant higher

fraction of Sy2s having a close neighbour within projected distance of 75 hˉ¹ kpc and up to δυ≤600km/s

Our spectroscopic observations mB≤18.5

2.1 m telescope Guillermo Haro observatory in

Cananea, operated by INAOE Faint Object Spectrograph and

Camera (LFOSC) 4200 – 9000 Å 15 Å sp. resolution

Large scale environment(radius 1Mpc, δυ≤1000km/s)

‹ρ›=∫ Φ(L)dL

Δρ= ────

Significant difference between Sy1-Sy2, but not between Seyferts-controls.

WHY?

∞

Lmin(r)

ρ - ‹ρ›

‹ρ›BECAUSE

Sy1s tend to live in earlier type galaxies than Sy2s and

earlier typegalaxies are more clustered

than late type.(Willmer, da Costa and

Pellegrini 1998)

Conclusions

1. Significantly more Sy2 galaxies have a close neighbour within a projected separation of 75 hˉ¹ kpc and δυ≤600 km/sec

2. Maybe this is correlated with different types of activity.

3. In large scales Sy1s tend to live in more dense areas.

4. Maybe this is due to different morphological types of Seyfert’s hosts.

“Local and Large Scale Environment of Bright IRAS Galaxies”

Samples were compiled from the BIRG Survey by Soifer et al. 1989 and by Sanders et al. 1995.

87 BIRGs (0.008<z<0.018) 75 control galaxies.

Neighbours with mB≤15.5 (CfA2 & SSRS)

Significantly higher fraction of BIRGs have a close neighbor in SSRS/CfA in respect with their control sample galaxies .

Significantly higher fraction of BIRGs have a close neighbor in SSRS/CfA in respect with Seyfert galaxies.

Neighbours with mB ≤ 18.5 (our spectroscopy)

Sy1 : 14% 27% Sy2 : 27% 55% BIRGs: 42% 54%

55%54%

≈

Large Scale Analysis

BIRGs and Sy2s present a similar large scale environment (KS : 0.90)

BIRGs and Sy1s present different large scale environment (KS : 0.03).

Conclusion : BIRGs and Sy2s tend to live in less clustered environment than Sy1s.

Colour Analysis

Starbursts <30kpc < <100kpc x isolated

Sy2s <30kpc < <100kpc x isolated

Normals <30kpc < <100kpc xx isolated

Liners <30kpc < <100kpc x isolated

Scenario : 1. Starburst activity is

higher when interactions are stronger.

2. Neighbor moves away starburst activity ceases and Sy2 nuclei appears.

3. When all interaction is over Sy1 nuclei appears.

(Krongold et al. 2002,2003)

Colour Analysis

Other studies about the feeding of AGNs & Starbursts and the AGN/Starburst connectionIn favour Against

1. Storchi-Bergmann et al.2001

2. Sorrentino, Radovich, Rifatto 2006

3. Sol-Alonso et al. 2007

4. Gonzalez et al. 2008

1. Miller et al. 2003

2. Schmitt 2001

3. Li & Kauffman 2006

4. Li et al. 2008

Induced Nuclear Activityin

mixed-morphology (E+S) galaxy pairs

J. Jesús González, Yair Krongold, Deborah Dultzin, Hector Hernandez-Toledo, Erendira Huerta, Lorenzo Olguin, Paola Marziani & Irene Cruz-Gonzalez 2008

40% of spirals in isolated (E+S) pairs show nuclear activity

(as compared to 20% in random fields including low luminosity LINERs found by Ho et al. 1997)

Only ONE out of 39 clear-cut AGN in the sample is type1. 2.6% frequency is too low to be explained by

obscuration/orientation effect only

NOW Detailed spectroscopic analysis of all the neighbors

around the subsamples in search of possible activity. (2m telescopes, GHAO & OAN-SPM)

Optical photometry (B & R) of all galaxies. (0.84m & 1.5m telescope, OAN-SPM)

Infrared photometry in search of activity and interactions (2m + CANICA, GHAO)

THANK YOU

What follows? Optical photometry (B & R) of all galaxies.

(0.84m & 1.5m telescope, OAN-SPM) Infrared photometry in search of activity and

interactions (2m + CANICA, GHAO)

THANK YOU