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Kink oscillations in coronal magnetic loops may be heating the ions in the sun's corona up to 10 million K and beyond. Could such oscillations in supernova impart enough extra energy to protons to take them beyond the GZK limit?

A step closer to understanding why the sun's corona is so hot

A possible mechanism for excitation of kink oscillations of coronal loops by a flare

GrapefruitIsAwesome
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By mentioning supernova in a question about cosmic rays, I'm assuming you mean supernova remnants, which are believed to be the predominant source of galactic cosmic rays, rather than the supernovae themselves which I don't believe are expected to produce cosmic rays (as the acceleration timescale of the particles is many thousands of years). Under such assumption, the answer is almost certainly not.

The primary reason is due to what is called the Hillas criterion, which states that the Larmor radius (or gyroradius, if you prefer) of the particle, $R_L= E/qB$, should not exceed the size of the accelerator. Hence, we can invert the relationship to show that, $$E_\text{max}=qBR_\text{object}$$ Since a supernova remnant has a radius of $\sim10^{14}$ km and magnetic fields of a few microgauss, then the maximum energy ought to be in the TeV to PeV range. Once a particle exceeds that, it will leave the SNR and continue on its merry way at that energy (until it collides with a particle or with one of our space-based detectors).
In order to get to the GZK limit range (above EeV energies), you would need either an astoundingly large object (e.g., active galactic nuclei, gamma-ray bursts) or astoundingly large magnetic field (e.g., magnetars).

Kyle Kanos
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  • Doesn't the energy depend on how many shockwaves push the proton. https://youtu.be/aTBvPxQIFts?si=sXeoRexCAQOej4Jr –  Nov 05 '23 at 19:00
  • http://arxiv.org/pdf/1302.3307v1.pdf –  Nov 05 '23 at 19:07
  • Well in a SNR, there is only one outward shockwave, so it clearly cannot be "how many shockwaves". It actually depends on the number of crossing of the shock interface the particle makes, cf. this Q&A I answered. – Kyle Kanos Nov 05 '23 at 19:17
  • See also this Q&A and this answer of mine to an unrelated question to the post at hand. – Kyle Kanos Nov 05 '23 at 19:18
  • I think that magnetars and blazers for example would emit the most energetic rays along a preferred orientation of their magnetic fields. I expect with time Ray detectors and telescopes around the world will reveal which magnetic objects in the sky have the correct orientation relative to Earth. –  Nov 05 '23 at 19:54