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Fermi Catalogs Facilitate Science
Astronomical catalogs provide a starting point for research, as shown in the box to the right. Because the Fermi instruments survey the sky continuously, they are ideally suited to producing both general and specialized catalogs.
The Fermi Science Support Center makes these catalogs available. See: http://fermi.gsfc.nasa.gov/ssc/data/access/
Ways in Which Catalogs Enable Scientific Research
- Discovery - unassociated sources are either previously unknown members of known source classes or something entirely new
- Population Studies - properties of whole classes of sources, such as their luminosity functions
- Correlated Variability Studies - compare activity in the gamma-ray band with multiwavelength observations; also ultra high-energy cosmic rays/high-energy neutrinos/gravitational waves
- Source Sample - to probe the Extragalactic Background Light/Inter-Galactic Magnetic Field
- Contribution - of Active Galactic Nuclei to the extragalactic diffuse gamma-ray background
The Third Fermi LAT Source Catalog (3FGL)
The 3FGL catalog, shown above in Galactic coordinates, contains 3033 gamma-ray sources seen by Fermi's Large Area Telescope at energies above 100 MeV. The table below shows the demographics of the high-energy gamma-ray sky. The LAT catalog defines firmly identified sources as those recognized by spatial morphology, periodicity, or correlated variability with other wavelengths. The associated sources are statistically related to known objects based primarily on sky location. + Learn More
* Includes binaries, nova, globular clusters, and star-forming regions
|Pulsar Wind Nebulae (PWNe)
|Supernova Remnants (SNRs)
|Quasars (steep and soft spectrum)
|BL Lac Blazars
|Flat Spectrum Radio Quasars
|Other Active Galactic Nuclei
|Normal & Starburst Galaxies
The Second Fermi GBM Gamma-ray Burst Catalog
The Second GBM gamma-ray burst catalog, shown above in Celestial coordinates, contains 953 gamma-ray bursts. Long bursts have duration greater than 2 second; short bursts have duration less than 2 seconds.
There is also a table of GRBs that have high-energy components detected by the LAT. This table is kept up-to-date by the LAT instrument team.
Wide Variety of Specialized Catalogs
In addition to all-sky catalogs, the instrument teams have performed more specialized analyses, focusing on specific source classes and using careful, systematic treatment of all the class members. As a result there are several publicly-available catalogs that are useful for studies of both individual sources as well as entires source populations.