In the scope of the Physics Beyond Colliders studies, the gamma-factory initiative proposes the use of partially stripped ions as a driver of a new type of high-intensity photon source in CERN Large Hadron Collider (LHC). In 2018, the LHC accelerated and stored partially stripped ${{}^{208}\mathrm{Pb}}^{81+}$ ions for the first time. The collimation system efficiency recorded during this test was found to be prohibitively low, so that only a very low-intensity beam could be stored without the risk of triggering a beam dump when regular, minor beam losses occur. The worst losses were localized in the dispersion suppressor of the betatron-cleaning insertion. This article presents an analysis to understand in detail the source of these losses. Based on this understanding, possible mitigation measures that could significantly improve the cleaning efficiency and enable regular operation with partially stripped ions in the future are developed.

中文翻译：

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CERN大型强子对撞机中部分剥离离子的准直

在“超越碰撞机的物理学”研究范围内，伽马工厂计划提议在CERN大型强子对撞机（LHC）中使用部分剥离的离子作为新型高强度光子源的驱动器。2018年，大型强子对撞机加速并部分剥离存储${{}^{208}\mathrm{铅含量}}^{81+}$离子。发现在该测试期间记录的准直系统效率非常低，因此，当发生规则的较小的光束损耗时，只能存储非常低强度的光束，而没有引发光束倾泻的风险。损失最严重的部分是在电子感应加速器清洁装置的色散抑制器中。本文提出了一项分析，以详细了解这些损失的来源。基于这种认识，开发了可能的缓解措施，这些措施可以显着提高清洁效率并在将来使部分被剥离的离子能够正常运行。