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arXiv · 1612.02056

Giant Terahertz Pulses Generated by Relativistic Beam in a Dielectric Channel

G. Stupakov·S. Gessner
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Abstract

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 $\gamma$ squared (in contrast to the scaling $\ln\gamma$ 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.

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G. Stupakov, S. Gessner. 2016-12-06. Giant Terahertz Pulses Generated by Relativistic Beam in a Dielectric Channel. https://arxiv.org/abs/1612.02056

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