Electron self-injection for the acceleration in laser-pulse-wakes in the   presence of a `strong' external magnetic field
  An external static magnetic field with its strength B~10T may result in the laser wake wave-breaking upon changing the electron motion in the vicinity of maximal density ramp of a wave period. This, as shown by numerical simulations, can change the resonance character of the electron self-injection in the laser wake-field; a total charge loaded in the acceleration phase of laser pulse wake can be controlled by a proper choice of the magnetic field strength. 
A. Zhidkov, T. Hosokai, S. Masuda, Y. Oishi, T. Fujii, R. Kodama
physics.plasm-ph physics.acc-ph