"Galactic cosmic rays consist of protons, electrons and ions, most of which are believed to be accelerated to relativistic speeds in supernova remnants1, 2, 3. All components of the cosmic rays show an intensity that decreases as a power law with increasing energy (for example as E-2.7). Electrons in particular lose energy rapidly through synchrotron and inverse Compton processes, resulting in a relatively short lifetime (about 105 years) and a rapidly falling intensity, which raises the possibility of seeing the contribution from individual nearby sources (less than one kiloparsec away)4." Nature 456, 362-365 (20 November 2008)

 

Read More: An excess of cosmic ray electrons at energies of 300–800 GeV, November 19, 2008

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