Beyond the myth of the supernova-remnant origin of cosmic rays

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The origin of Galactic cosmic-ray ions has remained an enigma for almost a century. Although it has generally been thought that they are accelerated in the shock waves associated with powerful supernova explosions—for which there have been recent claims of evidence—the mystery is far from resolved. In fact, we may be on the wrong track altogether in looking for isolated regions of cosmic-ray acceleration.

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Figure 1: Possible γ-ray emission from an SNR shock wave.


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Part of this work was carried out while the author was a fellow at the National Academy of Sciences. The support of a NASA Long Term Space Astrophysics grant is gratefully acknowledged.

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Correspondence to Yousaf Butt.

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Butt, Y. Beyond the myth of the supernova-remnant origin of cosmic rays. Nature 460, 701–704 (2009) doi:10.1038/nature08127

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