Transversal Deflection of Electrons Moving in Parallel with Linearly Polarized Laser Beam and its Application

The motion of electrons in linearly polarized laser beams in a finite length interaction region and then on a field free drift length is investigated. It is shown that in the interaction region the trajectories of the electrons are almost straight lines with very small oscillations. In the drift region the electrons acquire significant transversal deflection that allows to carry out the measurement of the length and longitudinal particle distribution of femtosecond bunches. The dependence of this deflection upon the electron energy, interaction region length, etc is studied. The principles of the construction of femtosecond oscilloscopes are discussed.