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arXiv · 2505.14111

Instabilities in Linear Accelerators

Massimo Ferrario·Mauro Migliorati·Luigi Palumbo
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Abstract

As a charged particle beam moves through perfectly conducting structures with varying cross-sectional boundaries - such as RF cavities, tapers, bellows, kickers, ... - it induces both longitudinal and transverse electromagnetic fields called wakefields. In this lecture, we explore the fundamental characteristics of wakefields and illustrate key concepts using simple cases in cylindrical geometry, including a perfectly conducting pipe and the resonant modes of an RF cavity. Finally, we examine how wakefields influence beam dynamics in a LINAC, focusing on beam breakup instabilities and potential mitigation strategies.

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Massimo Ferrario, Mauro Migliorati, Luigi Palumbo. 2025-05-20. Instabilities in Linear Accelerators. https://arxiv.org/abs/2505.14111

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