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arXiv · 0910.1298

Third Harmonic Cavity Modal Analysis

B. Szczesny·I. R. R. Shinton·R. M. Jones
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Abstract

Third harmonic cavities have been designed and fabricated by FNAL to be used at the FLASH/XFEL facility at DESY to minimise the energy spread along the bunches. Modes in these cavities are analysed and the sensitivity to frequency errors are assessed. A circuit model is employed to model the monopole bands. The monopole circuit model is enhanced to include successive cell coupling, in addition to the usual nearest neighbour coupling. A mode matching code is used to facilitate rapid simulations, incorporating fabrication errors. Curves surfaces are approximated by a series of abrupt transitions and the validity of this approach is examined

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B. Szczesny, I. R. R. Shinton, R. M. Jones. 2009-10-07. Third Harmonic Cavity Modal Analysis. https://arxiv.org/abs/0910.1298

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