Physical Sciences and Mathematics Commons^™

Diffusive Compression Acceleration Of Energetic Particles With An Application To Shock Acceleration Near Injection Energies, Ming Zhang

Aerospace, Physics, and Space Science Faculty Publications

The behavior of energetic charged particles accelerated by a continuous plasma compression profile is explored in the framework of diffusion. At high enough energies, the accelerated particles have a power-law spectrum with a slope generally steeper than a shock spectrum with the same compression ratio. The spectral slope depends on the ratio of the diffusion coefficient to the product of the upstream plasma speed and the thickness of the compression region. In the limit of large diffusion, the spectrum becomes identical to that of diffusive shock acceleration, and when diffusion is small enough, it is consistent with adiabatic acceleration by …