Dissipation of Hydromagnetic Waves on Energetic Particles: Impact on Interstellar Turbulence and Cosmic Ray Transport

The diffusion of galactic cosmic rays (CR) is considered. It is anticipated that the nonlinear MHD cascade sets the power-law spectrum of turbulence from the principle scale 100 pc to much smaller scales. We found that the dissipation of waves due to the resonant interaction with energetic particles may terminate the cascade at less than 1.e13 cm. The shape of CR diffusion coefficient that was found may explain the observed peaks of secondary to primary nuclei ratios at a few GeV/n.