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Accession Number DE2012-1045803
Title Search for Spatially Extended Fermi-LAT Sources Using Two Years of Data.
Publication Date Jul 2012
Media Count 74p
Personal Author A. Allafort A. Drlica-Wagner J. Ballet J. Cohen-Tanugi J. Lande K. Bechtol M. Ackermann T. H. Burnett
Abstract Spatial extension is an important characteristic for correctly associating (gamma)-ray-emitting sources with their counterparts at other wavelengths and for obtaining an unbiased model of their spectra. We present a new method for quantifying the spatial extension of sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi). We perform a series of Monte Carlo simulations to validate this tool and calculate the LAT threshold for detecting the spatial extension of sources. We then test all sources in the second Fermi-LAT catalog (2FGL) for extension. We report the detection of seven new spatially extended sources.
Keywords Detection
Fermi gamma ray space telescope
Gamma ray sources
Monte Carlo method
Supernova remnants

Source Agency Technical Information Center Oak Ridge Tennessee
NTIS Subject Category 46 - Physics
54C - Astrophysics
Corporate Author Stanford Linear Accelerator Center, CA.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1226
Contract Number DE-AC02-76SF00515

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