Further evidence favouring the single source model for cosmic rays

A detailed examination has been made of recent estimates of the energy spectra of the different mass components of cosmic rays. Although the results depend on the interaction models used, sufficient insight is provided to allow us to confirm that the spectral changes needed to explain the data are too sharp to be accounted for by the process of conventional Galactic Modulation, i.e. a gradual leaking out of particles from the Galaxy. Instead they fit well our 'single source model' which explains features in the spectra as being due to oxygen nuclei (at similar to3 PeV) and iron nuclei (at 12 PeV). The presence of further structure in the spectrum beyond about 50 PeV is hinted at. (C) 2004 Elsevier B.V. All rights reserved.