The Fraction of Compton-thick AGN
It is $38^{+8}_{-7}\%$
Puerto Varas / Mar 2015
Johannes Buchner
astro-ph:1501.02805in collaboration with A. Georgakakis, K. Nandra,
M. Brightman, ML. Menzel, L. Hsu, M. Salvato, C. Rangel, J. Aird, A. Merloni
Data
2000 AGN from
- CDFS 4Ms
- AEGIS-XD
- COSMOS
- XMM-XXL (20 sq deg)
Diff. to previous works
| Aird+10 | Ueda+14 | Buchner+15 | |
|---|---|---|---|
| sources without counterpart | yes | yes | |
| photometric redshift uncertainty | yes | yes | yes |
| +systematic uncertainty | yes | ||
| absorption model | yes | yes | |
| soft scattering component | (fixed) | yes | |
| Compton reflection component | yes |
Diff. to previous works
| Aird+10 | Ueda+14 | Buchner+15 | |
|---|---|---|---|
| Handles ambiguous solutions | N/A | yes | |
| Assumed column density distribution | N/A | LDDE | free |
| Assumed evolution model | LDDE | LDDE | free |
Results
Conclusions: AGN Model
- Fraction of obscured AGN: $77^{+4}_{-5}\%$
- Fraction of CT AGN: $38^{+8}_{-7}\%$
- Luminosity-dependence evolves with z -- mass downsizing?