Probing the Geometry and Physics of the Emission Region in Active Galactic Nuclei using hard X-ray & Gamma-ray Observations

Technical Report · Wed Aug 25 00:00:00 EDT 2010

DOI:https://doi.org/10.2172/992928· OSTI ID:992928

Woods, Natasha

The X-ray spectra of {approx}200 AGN collected from Swift-BAT were analyzed to test the Unified Model for AGN. Specifically, the photon indices, high energy cutoffs, and reflection components of Sy1 and Sy2 were compared. Under the Unified Model, the photon indices and reflection components for Sy1 should be larger than Sy2 and the high energy cutoffs should be the same. Fitting a simple power law model to the sample spectra proved to be insufficient. The PEXRAV model fit the spectra of the Sy1 and Sy2 significantly better, indicating that a reflection component and/or high energy cutoff exists as the Unified Model expects. Using both the simple power law and PEXRAV models it was concluded that in the population studied, Sy1 had a larger photon index than Sy2, as expected by the Unified Model. For Sy1 and Sy2, the reflection components were found to be compatible, but given the large errors, this finding cannot be said to be evidence against the Unified Model. However, it was concluded that Sy1 and Sy2 have different high energy cutoffs, which is unexpected under the Unified Model.

• Research Organization: SLAC National Accelerator Laboratory (SLAC)
• Sponsoring Organization: US DOE Office of Science (DOE SC)
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 992928
• Report Number(s): SLAC-TN-10-021
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Astrophysics
GEOMETRY
NUCLEI
PHOTONS
PHYSICS
REFLECTION
SPECTRA
UNIFIED MODEL
X-RAY SPECTRA