Fermi Gamma-ray Space Telescope

LAT Specifications & Performance

Quantity LAT (Minimim Spec.) EGRET
Energy Range 20 MeV - 300 GeV 20 MeV - 30 GeV
Peak Effective Area1 > 8000 cm2 1500 cm2
Field of View > 2 sr 0.5 sr
Angular Resolution2
 
< 3.5° (100 MeV)
< 0.15° (>10 GeV)
5.8° (100 MeV)
 
Energy Resolution3 < 10% 10%
Deadtime per Event < 100 μs 100 ms
Source Location Determination4 < 0.5' 15'
Point Source Sensitivity5 < 6 x 10-9 cm-2 s-1 ~ 10-7 cm-2 s-1

1 After background rejection
2 Single photon, 68% containment, on-axis
3 1-σ, on-axis
4 1-σ radius, flux 10-7 cm-2 s-1 (>100 MeV), high |b|
5> 100 MeV, at high |b|, for exposure of one-year all sky survey, photon spectral index -2