Fermi Large Area Telescope Observations of the Cosmic-Ray Induced gamma-ray Emission of the Earth's Atmosphere

Dec, 2009
13 pages
Published in:
  • Phys.Rev.D 80 (2009) 122004
e-Print:
Report number:
  • SLAC-PUB-14880
Experiments:

Citations per year

2009201320172021202402468101214
Abstract: (arXiv)
We report on measurements of the cosmic-ray induced gamma-ray emission of Earth's atmosphere by the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. The LAT has observed the Earth during its commissioning phase and with a dedicated Earth-limb following observation in September 2008. These measurements yielded 6.4 x 10^6 photons with energies >100MeV and ~250hours total livetime for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission - often referred to as Earth albedo gamma-ray emission - has a power-law shape up to 500 GeV with spectral index Gamma = 2.79+-0.06.
Note:
  • Accepted for publication in PRD
  • 96.50.sd
  • 96.50.S-
  • 92.60.hx
  • 96.50.sf