Session B1 - Cosmic Rays: From Knee to the Ankle and Beyond.
INVITED session, Saturday morning, April 28
Grand Ballroom North/Central, Renaissance Hotel
Ultra-high energy cosmic rays offer a unique opportunity to test cosmic ray acceleration mechanisms at extreme conditions. I will present recent results of the quasilinear cosmic ray transport theory with respect to resonant wave-particle acceleration, both in the interstellar medium and in powerful extragalactic sources as active galactic nuclei and gamma-ray bursts. It is shown that observing and modelling the cosmic plasma turbulence beyond the magnetostatic approximation is crucial for the understanding of cosmic ray acceleration. In particular, higher harmonics resonant interactions with obliquely propagating MHD waves play an important role for the acceleration of cosmic rays beyond the knee.