Upgrade of the TCDQ: A dumping protection system for the LHC

In the context of the LHC, an asynchronous beam dump could be destructive. In order to ensure the safety of the machine and its surroundings a model of the TCDQ dump has been designed. The length of the TCDQ dump is increased by 50% and its material distribution along its length is changed from graphite to a carbon composite that clearly withstands higher stresses then its counterpart. There are two different density composites used along the dump‘s length in a similar distribution than that of the TCDS, varying from high density to low then back to high. The power deposition within the duration of a pulse is given by FLUKA simulations and is used to predict temperature and stress distributions in space and time. The results are compared with previous studies in which graphite material was used. The difference in the thermal expansion coefficient of the two materials explains the reduced stresses in the newer design. Due to the high cost of carbon composites an alternative solution is thought without jeopardizing the new design. The TCDQ diluter design represents one of the main protection elements for the LHC beam dumping system (Weterings, et al., 2012).

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