These are the slides for my oral presentation

1. Is the cluster environment
quenching the Seyfert activity in
elliptical and spiral galaxies?
Maria Luiza Linhares Dantas (IAG-USP)
On behalf of the COIN Collaboration
R. S. de Souza (UNC), M. L. L. Dantas (USP), A. Krone-Martins (UL), E. Cameron
(Oxford), P. Coelho (USP), M. W. Hattab (Virginia Univ.), M. de Val-Borro
(Princeton), J. M. Hilbe (Arizona, JPL), J. Elliott (Harvard) and A. Hagen (PSU)

2. Outline
1. Introduction
2. Goal
3. Dataset
4. Methodology
5. Results
6. Conclusions
7. The COIN Collaboration
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3. Introduction

4. Problem
Is the presence of AGN activity linked to its
host galaxy environment?
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5. Problem
Is the presence of AGN activity linked to its
host galaxy environment?
Is the mass of the cluster important?
4

6. Problem
Is the presence of AGN activity linked to its
host galaxy environment?
Is the mass of the cluster important?
Does the galaxy morphology play a role?
4

7. Previous Works
Pimblet et al. (2013)
AGN fraction x Radius/R200
5

8. Previous Works
Villarroel & Korn (2014)
The fraction of AGN residing in spiral hosts depends on the presence of a neighbor
galaxy.
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9. Goal

10. Goal
Can we model the probability of a galaxy
hosting an AGN given the 3 following
parameters?
- Cluster mass (M200)
- Cluster centric distance (R200) - proxy for
environment
- morphology (elliptical & spiral)
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11. Paper
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12. Dataset

13. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
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14. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
- 0.015 ≤ z ≤ 0.1 (local universe)
11

15. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
- 0.015 ≤ z ≤ 0.1 (local universe)
- Haloes w/ at least 10 members
11

16. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
- 0.015 ≤ z ≤ 0.1 (local universe)
- Haloes w/ at least 10 members
- 13.4 ≤ log M200 ≤ 14.6
11

17. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
- 0.015 ≤ z ≤ 0.1 (local universe)
- Haloes w/ at least 10 members
- 13.4 ≤ log M200 ≤ 14.6
- K-correction, extinction correction, etc.
11

18. Dataset
- SDSS DR7 + DR12 + objects + Galaxy Zoo Morph.
Classification
- 0.015 ≤ z ≤ 0.1 (local universe)
- Haloes w/ at least 10 members
- 13.4 ≤ log M200 ≤ 14.6
- K-correction, extinction correction, etc.
- Final catalog: 32K+ objects
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19. Sample Selection
We need an AGN-host sample and a AGN-free
sample for control.
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20. Sample Selection
We need an AGN-host sample and a AGN-free
sample for control.
Which objects have AGN for sure?
12

21. Sample Selection
We need an AGN-host sample and a AGN-free
sample for control.
Which objects have AGN for sure?
Which objects do not have AGN for sure?
12

22. Sample Selection
We need an AGN-host sample and a AGN-free
sample for control.
Which objects have AGN for sure?
Which objects do not have AGN for sure?
12

23. Methodology

24. Propensity Score Matching - what is it?
Take home message:
We select a subsample with twin galaxies in each category (with
or without AGN).
Credits: Carson Analytics
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25. Propensity Score Matching
Red: ellipticals; Cyan: spirals
Light colors (red and cyan): positive AGN
Dark colors (red and cyan): negative AGN 15

26. Seyfert Galaxies of the Sample
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27. Logistic Regression - Bernoulli Distribution
Suitable for binary data, i.e. flipping a coin or
modelling the presence or not of AGN.
f(k; p) =
{
p, if k = 0
1 − p, if k = 1
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28. "Linear" vs. Logistic Regression
Credits: Bayesian Models For Astropysical Data - J.M. Hilbe, R.S.de Souza, E. Ishida.
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29. Results

30. Logistic Regression
Slice of the 3D regression: log M200, R/R200, and probability.
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31. Conclusions

32. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
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33. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
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34. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
Moreover...
- Our technique is a leap forward in terms of data analysis
and interpretation;
22

35. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
Moreover...
- Our technique is a leap forward in terms of data analysis
and interpretation;
- Why are ellipticals loosing their AGN while falling into the
gravitational potential?
22

36. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
Moreover...
- Our technique is a leap forward in terms of data analysis
and interpretation;
- Why are ellipticals loosing their AGN while falling into the
gravitational potential?
Our hypothesis: interactions, such as ram pressure;
22

37. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
Moreover...
- Our technique is a leap forward in terms of data analysis
and interpretation;
- Why are ellipticals loosing their AGN while falling into the
gravitational potential?
Our hypothesis: interactions, such as ram pressure;
- For spirals: the bulge holds effectively the gas more
tightly around those few kpc around the central SMBH.
22

38. Conclusions
So, is the cluster environment quenching the Seyfert activity
in elliptical and spiral galaxies?
Answer:
Yes, for ellipticals. No, for spirals.
Moreover...
- Our technique is a leap forward in terms of data analysis
and interpretation;
- Why are ellipticals loosing their AGN while falling into the
gravitational potential?
Our hypothesis: interactions, such as ram pressure;
- For spirals: the bulge holds effectively the gas more
tightly around those few kpc around the central SMBH.
- Caveat: no disentanglement among spirals. –> Bars,
rings, etc. may be important to feed the central SMBH.
22

39. Bonus

40. The COIN Collaboration
COIN: Cosmostatistics Initiative (funded in 2014 by
Rafael S. de Souza)
Working group of the International Astrostatistics
Association (IAA, funded in 2012 by Joseph M. Hilbe)
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41. COIN Residence Program 2
Where? Cowes, Isle of Wight, UK.
When? October 2015.
Who? All these great people:
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42. COIN Residence Program 2
How? One house, one week! Like this:
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43. COIN Residence Program 2
How? One house, one week! Like this:
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44. Thank you!