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SWIFT BAT Survey of AGNWe present the results1 of the analysis of the first 9 months of data of the Swift BAT survey of AGN in the 14-195 keV band. Using archival X-ray data or follow-up Swift XRT observations, we have identified 129 (103 AGN) of 130 objects detected at [b] > 15deg and with significance > 4.8-delta. One source remains unidentified. These same X-ray data have allowed measurement of the X-ray properties of the objects. We fit a power law to the logN - log S distribution, and find the slope to be 1.42+/-0.14. Characterizing the differential luminosity function data as a broken power law, we find a break luminosity logL*(ergs/s)= 43.85+/-0.26. We obtain a mean photon index 1.98 in the 14-195 keV band, with an rms spread of 0.27. Integration of our luminosity function gives a local volume density of AGN above 10(exp 41) erg/s of 2.4x10(exp -3) Mpc(sup -3), which is about 10% of the total luminous local galaxy density above M* = -19.75. We have obtained X-ray spectra from the literature and from Swift XRT follow-up observations. These show that the distribution of log nH is essentially flat from nH = 10(exp 20)/sq cm to 10(exp 24)/sq cm, with 50% of the objects having column densities of less than 10(exp 22)/sq cm. BAT Seyfert galaxies have a median redshift of 0.03, a maximum log luminosity of 45.1, and approximately half have log nH > 22.
Document ID
20080039128
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Tueller, J.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Mushotzky, R. F.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Barthelmy, S.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Cannizzo, J. K.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Gehrels, N.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Markwardt, C. B.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Skinner, G. K.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Winter, L. M.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 24, 2013
Publication Date
January 1, 2008
Subject Category
Astronomy
Distribution Limits
Public
Copyright
Public Use Permitted.
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