| Paper | Title | Page |
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| TUPMP018 | Feasibility Tests of a Vacuum System for SPring-8-II | 1272 |
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| For SPring-8-II, the major upgrade of SPring-8, a test half-cell including permanent/electro magnets and a vacuum system was constructed, and hardware feasibility tests have been performed since 2017. Features of the SPring-8-II vacuum system are 1) introduction of the concept of a stainless steel 12 m-long integral chamber (LIC) with a welded structure, and 2) adoption of ex-situ baking of the chamber. The 12 m LIC with a narrow aperture, flangeless structure and a minimum number of bellows was designed so that the vacuum system could be installed without interference with the magnets of a narrow bore diameter aligned on girders with a severe packing factor. For replacement of the existing system with a new one in a short black-out period, the 12 m LIC is planned to be moved into the accelerator tunnel with keeping ultra-high vacuum (UHV) by closing thin gate valves at both ends, after evacuation to UHV by ex-situ baking and NEG activation. This presentation will overview the vacuum system, mainly the 12 m LIC, developed for the test half-cell, and describe the vacuum performance and the result of the assembly test conducted with the permanent/electro magnets. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPMP018 | |
| About • | paper received ※ 15 May 2019 paper accepted ※ 17 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| WEPGW027 | Evaluation and Reduction of Influence of Filling Pattern on X-Ray Beam Position Monitors for SPring-8 | 2526 |
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SPring-8 constantly provides various several-bunch mode operations, which combine single bunches and train bunches. Recently, influence of filling pattern on the accuracy of the XBPMs became apparent, so that we started a systematic evaluation. It was found that the influence was caused by suppression of current signal due to space charge effect, which could be quantified by observing a behaviour of the current signal while changing the voltage of photoelectron collecting electrodes. In order to mitigate the space charge effect, we examined some methods, such as, changing operation parameters of the XBPMs and the undulators. As a result, we successfully reduced the influence of filling pattern.
* H. Aoyagi et al., Proc. of PASJ2018 WEOL06 http://www.pasj.jp/webpublish/pasj2018/proceedings/PDF/WEOL/WEOL06.pdf http://www.pasj.jp/webpublish/pasj2018/proceedings/PDF/WEOL/WEOL06oral.pdf |
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| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPGW027 | |
| About • | paper received ※ 10 May 2019 paper accepted ※ 17 May 2019 issue date ※ 21 June 2019 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |