Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV
Abstract
We present the results of our analysis of cosmic-ray electrons using about 8×106 electron candidates detected in the first 12 months on-orbit by the Fermi Large Area Telescope. This work extends our previously published cosmic-ray electron spectrum down to 7 GeV, giving a spectral range of approximately 2.5 decades up to 1 TeV. We describe in detail the analysis and its validation using beam-test and on-orbit data. In addition, we describe the spectrum measured via a subset of events selected for the best energy resolution as a cross-check on the measurement using the full event sample. Our electron spectrum can be described with a power law ∝E-3.08±0.05 with no prominent spectral features within systematic uncertainties. Within the limits of our uncertainties, we can accommodate a slight spectral hardening at around 100 GeV and a slight softening above 500 GeV.
- Publication:
-
Physical Review D
- Pub Date:
- November 2010
- DOI:
- 10.1103/PhysRevD.82.092004
- arXiv:
- arXiv:1008.3999
- Bibcode:
- 2010PhRvD..82i2004A
- Keywords:
-
- 96.50.sb;
- 95.35.+d;
- 95.85.Ry;
- 98.70.Sa;
- Composition energy spectra and interactions;
- Dark matter;
- Neutrino muon pion and other elementary particles;
- cosmic rays;
- Cosmic rays;
- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Experiment;
- High Energy Physics - Phenomenology
- E-Print:
- 20 pages, 23 figures, 2 tables, published in Physical Review D 82, 092004 (2010) - contact authors: C. Sgro', A. Moiseev