1. Mentors: Marco Ajello & Masaaki Hayashida
Probing the Geometry and Physics of the Emission Region of Active Galactic Nuclei Using Hard X-Ray Observations
Natasha Woods
Mentors: Marco Ajello & Masaaki Hayashida

2. Outline AGN & Unified Model Testing the Unified Model Results
Conclusions

3. Introduction AGN Classification
Majority of energy output unrelated to stellar processes
Compact regions, galaxy center, exceedingly luminous
Classification
Radio luminosity
Spectral properties

4. Unified Model for AGN All AGN are intrinsically the same
Perceived differences due to viewing orientation
SMBH, accretion disk, molecular torus, corona

5. Seyfert Galaxies

6. Evidence For & Against the Unified Model
Polarized broad emission lines in Sy2
Sy1 <---> Sy2
Electron temperature
Fraction of absorbed sources

7. X-ray Spectra
X-Rays
IC Radiation
Direct, Transmitted, Reflected

8. Reflection Component
IC reflection peak ~30keV, softening spectra (whiteboard)
Sy1 should have a larger reflection component and photon index than Sy2

9. High Energy Cut-off Corona's electrons expected to be thermal
Cut-offs for Sy1 and Sy2 should be compatible, corona's properties are independent of orientation

10. Relevance
~100% CXB
Constrain cosmological models and black hole physics

11. Sample Population ~200 sources Swift-BAT hard X-ray Survey
5 sigma significance level
3 years exposure
Unbiased, blind search

12. Models for Spectra
Simple power law model (SPL) fit to individual spectra in Xspec11

13. Photon Index Histograms

14. Gaussian and Weighted Averages
Gaussian poorly fit some data
Weighted Averages
based on errors
no model

15. Stacked Spectra
S/N, mean properties
SPL and PEXRAV fit to spectra

16. Results: SPL Histograms
(KS p-values)

17. Results: SPL & PEXRAV Stacked Spectra
PEXRAV>SPL
Photon Indices
Reflection
Energy Cut- off

18. Conclusion Photon Index Sy1 > Sy2 PEXRAV > SPL
Reflection compatible, large errors
Energy Cut-offs different
Future

19. Acknowledgements