Sketch of cosmic-ray physics

The origin and cause of acceleration of cosmic rays is somewhat uncertain, but the power-law energy spectrum suggests some kind of electromagnetic process 

Another view, equally consistent with the source abundances and better suited to account for the abundance of light elements like beryllium in stars of the Galactic halo (see below), is that dust particles in the supernova ejecta are the source of ions that are preferentially accelerated within the hot, tenuous gas of superbubbles surrounding regions of star formation (Lingenfelter, Ramaty Kozlovsky 1998). 

The initial spectrum of cosmic rays is expected to be a power law in the momentum p of particles, e.g. 

1 Hubert Reeves once summed up the similarity of cosmic-ray source and Solar-System abundances in the form of a graffito seen at times in Paris CRS = SS  

2 Sometimes identified earlier with the FIP effect (see Section 3.5.1). 

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