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arXiv · 2412.03202

Dielectric Loaded Waveguide Terahertz LINACs

Mostafa Vahdani·Moein Fakhari·Franz X. Kaertner
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Abstract

Dielectric loaded waveguides (DLWs) driven by multicycle terahertz (THz) pulses hold great promise as compact linear accelerators (LINACs) due to their ability to sustain higher breakdown fields at THz frequencies compared to conventional RF components. Precise control of the THz pulse's phase and group velocities within the DLW can be achieved by adjusting the dimensions of the dielectric tube. Optimization of the DLW parameters has to take various factors into account like initial electron energy, THz pulse energy available, THz pulse width, DLW dimensions, etc. To maximize the final kinetic energy of the accelerated electrons, this study presents a comprehensive analytical/numerical guideline for cylindrical DLW LINACs. Additionally, graphic representations are introduced to visualize optimal designs for varying initial electron and THz pulse energies. The provided guideline figures enable designers to tailor the accelerator to specific requirements, paving the way for potential advancements in THz-driven particle acceleration and offering cost-effective alternatives to conventional RF accelerators for various scientific, industrial, and medical applications.

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Mostafa Vahdani, Moein Fakhari, Franz X. Kaertner. 2024-12-04. Dielectric Loaded Waveguide Terahertz LINACs. https://arxiv.org/abs/2412.03202

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