1. Equations of Motion for an Ideal Plasma.
2. The guiding center approximation to charged particle motion
3. On the Origin of the Cosmic Radiation
4. For example, H. Alfvén,Cosmical Electrodynamics(Clarendon Press, Oxford, 1950).
5. For the nonrelativistic case and also for the static relativistic case this is equivalent to the invariance of the magnetic moment of the particle’s gyro motion. The invariance of p˔2∕B can be shown for a static field from Eqs. (1) and (2) and the invariance of the energy. It follows that the flux, φ = π(p˔c∕Be)2B, through the orbit of the particle is an invariant.