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arXiv · 0707.0539

Synchrotron Radiation Interferometer Calibration Check by Use of A Size Control Bump in KEKB

N. Iida·J. Flanagan·Y. Funakoshi·K. Oide
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Abstract

In KEKB, synchrotron radiation interferometers (SRMs) are used for measuring the transverse beam sizes. There is also a tool for enlarging the vertical beam size intentionally by making an asymmetric bump, called an ``iSize'' bump, at one of the strongest non-interleaved sextupole magnets in each KEKB ring. The calibrations of the SRMs were checked by comparing the measured vertical beam sizes with those calculated using the computer code ``SAD''. The obtained correction factors are 1.000$\pm$0.045 for HER and 0.971$\pm$0.060 for LER, which are consistent with the calibration factors of SRMs\cite{SRMcalib} within errors. Using the obtained calibration factor, x-y coupling of each ring was calculated .

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N. Iida, J. Flanagan, Y. Funakoshi, K. Oide. 2007-07-04. Synchrotron Radiation Interferometer Calibration Check by Use of A Size Control Bump in KEKB. https://arxiv.org/abs/0707.0539

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