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Abstract |
The increased precision of new cosmic ray (CR) experiments has revealed several
observational anomalies, i.e. deviations from the ``naive'' expectations in the diffusion
picture for CR propagation. After reviewing a more theoretical challenge for the simplest
diffusion picture, I argue that CRs diffuse strongly anisotropic. As a result, the number of
CRs sources contributing to the locally observed flux is strongly suppressed, and few local
CR source may dominate the CR flux. In particular, I show that the 2-3 Myr old source
required to explain the Fe60 sediments found in Earth's ocean crust can also explain
naturally the "positron excess" as well as the observed breaks at 200 GV in the CR primary
spectra. At higher energies, Vela may be responsible for the CR knee and the CR flux up to
the transition to extragalactic CRs.
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