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Fermi Large Area Telescope Second Source CatalogWe present the second catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24-month period. The Second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in 5 energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100 11eV to 100 GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely gamma-ray-producing source classes.
Document ID
20120016520
Document Type
Preprint (Draft being sent to journal)
Authors
Nolan, P. L. (Stanford Univ. Palo Alto, CA, United States)
Abdo, A. A. (George Mason Univ. Fairfax, VA, United States)
Ackermann, M. (Deutsches Elektronen-Synchrotron Zeuthen, Germany)
Ajello, M (Stanford Univ. Palo Alto, CA, United States)
Allafort, A. (Stanford Univ. Palo Alto, CA, United States)
Antolini, E (Istituto Nazionale di Fisica Nucleare Perugia, Italy)
Bonnell, J. (Maryland Univ. College Park, MD, United States)
Cannon, A. (University Coll. Dublin, Ireland)
Celik O. (Maryland Univ. College Park, MD, United States)
Corbet, R. (Maryland Univ. College Park, MD, United States)
Davis, D. S. (Maryland Univ. College Park, MD, United States)
DeCesar, M. E. (Maryland Univ. College Park, MD, United States)
Ferrara, E. C. (Maryland Univ. College Park, MD, United States)
Gehrels, N. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Harding, A. K. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Hays, E. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Johnson, T. E. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
McConville, W. (Maryland Univ. College Park, MD, United States)
McEnery, J. E (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Perkins, J. S. (Maryland Univ. College Park, MD, United States)
Racusin, J. L (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Scargle, J. D. (NASA Ames Research Center Moffett Field, CA, United States)
Stephens, T. E. (Wyle Labs., Inc. El Segundo, CA, United States)
Thompson, D. J. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Troja, E. (Maryland Univ. College Park, MD, United States)
Date Acquired
August 26, 2013
Publication Date
February 23, 2012
Subject Category
Astronomy
Report/Patent Number
GSFC.JA.7309.2012
Distribution Limits
Public
Copyright
Public Use Permitted.

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