2016/12/06 by Stupakov, G., Gessner, S.
#Accelerator Physics (physics.acc-ph) #FOS: Physical sciences #Plasma Physics (physics.plasm-ph)
paper · doi:10.48550/arxiv.1612.02056
We analyze the electromagnetic field of a short relativistic electron beam propagating in a round, hollow dielectric channel. We show that if the beam propagates with an offset relative to the axis of the channel, in a steady state, its electromagnetic field outside of the channel extends to large radii and carries an energy that scales as the Lorentz factor γ squared (in contrast to the scaling lnγ without the channel). When this energy is converted into a terahertz pulse and focused on a target, the electric field in the focus can greatly exceed typical values of the field that are currently achieved by sending beams through thin metallic foils.