The scattering mean free path of cosmic ray particles in isotropic damped plasma wave turbulence
1 Institut für Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universität Bochum, 44780 Bochum, Germany
2 University of Defence, Military Academy, Pavla Jurisica Sturma 33, 11000 Belgrade, Serbia
Received: 30 January 2013
Accepted: 3 May 2013
An analytical expression for the mean free path of single-charged cosmic ray particles, especially for positrons, is derived in isotropic plasma wave turbulence, where the crucial scattering of cosmic ray particles with small pitch-angle cosines is caused by resonant cyclotron interactions with oblique magnetosonic waves. In this calculation, viscous damping effects are included, which results in broadening of the resonance function. It is demonstrated that including resonance function broadening ensures a finite mean free path for cosmic ray energies, for which previously reported types of turbulence predicted an infinitely large mean free path.
Key words: scattering
© ESO, 2013