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Beam Coupling Impedances of Obstacles Protruding into Beam Pipe

Sergey S. Kurennoy
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Abstract

The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated analytically at frequencies for which the wavelength is large compared to a typical size of the obstacle. Simple formulas for a few important particular cases, including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. The analytical results are compared and agree with three-dimensional computer simulations. These results allow simple practical estimates of the broad-band impedance contributions from such discontinuities.

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Sergey S. Kurennoy. 1997-06-18. Beam Coupling Impedances of Obstacles Protruding into Beam Pipe. https://doi.org/10.1103/physreve.55.3529

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