An energy of 362 MJ is stored in each of the two LHC proton beams for nominal beam parameters. This will be further increased to about 700 MJ in the future high luminosity LHC (HL-LHC) and uncontrolled beam losses represent a significant hazard for the integrity and safe operation of the machine. In this paper, a number of failure mechanisms that can lead to a fast increase of beam losses are analyzed. Most critical are failures in the magnet protection system, namely the quench heaters and a novel protection system called coupling-loss induced quench (CLIQ). An important outcome is that magnet protection has to be evaluated for its impact on the beam and designed accordingly. In particular, CLIQ, which is to protect the new HL-LHC triplet magnets, constitutes the fastest known failure in the LHC if triggered spuriously. A schematic change of CLIQ to mitigate the hazard is presented. A loss of the beam-beam kick due to the extraction of one beam is another source of beam losses with a fast onset. A significantly stronger impact is expected in the upcoming LHC Run III and HL-LHC as compared to the current LHC, mainly due to the increased bunch intensity. Its criticality and mitigation methods are discussed. It is shown that symmetric quenches in the superconducting magnets for the final focusing triplet can have a significant impact on the beam on short timescales. The impact on the beam due to failures of the beam-beam compensating wires as well as coherent excitations by the transverse beam damper are also discussed.

中文翻译：

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大型强子对撞机快速故障以及未来的高亮度大型强子对撞机

362 MJ的能量存储在两个LHC质子束的每一个中，用于标称束参数。将来，高亮度LHC（HL-LHC）会进一步增加到约700 MJ，不受控制的光束损失会严重危害机器的完整性和安全操作。在本文中，分析了许多可能导致光束损耗快速增加的失效机制。最关键的是磁体保护系统的故障，即失超加热器和一种称为耦合损耗感应失超（CLIQ）的新型保护系统。一个重要的结果是，必须评估磁体保护装置对梁的影响并进行相应设计。特别是，用于保护新的HL-LHC三重态磁铁的CLIQ如果是偶然触发的，则是LHC中最快的已知故障。给出了CLIQ减轻危害的示意性更改。由于一个光束的引出而导致的光束束突跳的损失是另一个起步快的光束损失的来源。与目前的大型强子对撞机相比，预计即将到来的大型强子对撞机运行III和HL-LHC将产生更大的影响，这主要是由于束强度增加。讨论了其重要性和缓解方法。结果表明，用于最终聚焦三重态的超导磁体中的对称淬火可以在短时间内对电子束产生重大影响。还讨论了由于束补偿梁的故障以及横向束阻尼器引起的相干激发对束的影响。由于一个光束的引出而导致的光束束突跳的损失是另一个起步快的光束损失的来源。与目前的大型强子对撞机相比，预计即将到来的大型强子对撞机运行III和HL-LHC将产生更大的影响，这主要是由于束强度增加。讨论了其重要性和缓解方法。结果表明，用于最终聚焦三重态的超导磁体中的对称淬火可以在短时间内对电子束产生重大影响。还讨论了由于光束补偿梁的故障以及横向光束阻尼器的相干激发而对光束造成的影响。由于一个光束的引出而导致的光束束突跳的损失是另一个起步快的光束损失的来源。与目前的大型强子对撞机相比，预计即将到来的大型强子对撞机运行III和HL-LHC将产生更大的影响，这主要是由于束强度增加。讨论了其重要性和缓解方法。结果表明，用于最终聚焦三重态的超导磁体中的对称淬火可以在短时间内对电子束产生重大影响。还讨论了由于光束补偿梁的故障以及横向光束阻尼器的相干激发而对光束造成的影响。讨论了其重要性和缓解方法。结果表明，用于最终聚焦三重态的超导磁体中的对称淬火可以在短时间内对电子束产生重大影响。还讨论了由于束补偿梁的故障以及横向束阻尼器引起的相干激发对束的影响。讨论了其重要性和缓解方法。结果表明，用于最终聚焦三重态的超导磁体中的对称淬火可以在短时间内对电子束产生重大影响。还讨论了由于束补偿梁的故障以及横向束阻尼器引起的相干激发对束的影响。