Inertial Alfvén waves and acceleration of electrons in nonuniform magnetic fields

We present results from self-consistent simulations of the electron response to shear Alfvén pulses in the presence of non-uniform magnetic fields and the associated mirror force. We discuss how energies of resonantly accelerated beam particles are affected by the local phase velocity of the pulse, and show that time-of-flight models are inadequate for describing electron acceleration since the acceleration can occur at more than one location along the field line as the pulse propagates toward the ionosphere. We also demonstrate that electron conics in low-altitude satellite observations of electron acceleration can be explained in terms of field-aligned inertial Alfvén wave pulses, without the requirement of a static potential drop or a standing Alfvén wave structure.