What is the 'negative legacy' that plagues CERN with the update of the Large Hadron Collider?


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Department for Business, Innovation and Skills

The world's largest collider ' Large Hadron Collider (LHC) ', which the European Nuclear Research Organization (CERN) is proud of, is used to elucidate the 'Big Bang' and 'Dark Matter ' that are the beginnings of the universe. It is expected as a device that solves many difficult problems. However, there are some non-negligible problems in upgrading to improve the performance of the Large Hadron Collider, which seems to be a big headache for CERN.

CERN Engineers Have to Identify and Disconnect 9,000 Obsolete Cables | Motherboard
http://motherboard.vice.com/en_uk/read/cern-engineers-have-to-identify-and-disconnect-9000-obsolete-cables

The Large Hadron Collider is a magnificent experimental facility that creates new particles by accelerating particles in opposite directions at the speed of light and colliding them in a circular tunnel. It is a facility that has made many achievements such as contributing to the observation of 'Higgs boson ' by Dr. Peter Higgs, who won the 2013 Nobel Prize in Physics. It is a huge experimental device with a lap of about 27km.



The LHC is regularly inspected and updated to improve performance, but the facility is so huge that it can be shut down for several years when conducting large-scale experiments. Such a LHC is scheduled for a large-scale upgrade within a few years, but CERN scientists and engineers are suffering from the 'negative legacy' that makes the upgrade work difficult.

The negative legacy is the innumerable cables in the injector part just before the accelerator. The LHC injectors have undergone major functional updates, with changes being introduced and discontinued each time. However, the old cable was not removed each time, and most of it was left unconnected. The number is estimated to be 9,000.



Replacing the cable of the injector part of the LHC, which is the most expensive 'experimental device' in the world, may not be able to carry out the experiment normally if it is mistaken, and in some cases, there is a risk of serious damage to the device. Therefore, it is not difficult to imagine that caution and accuracy are required.

CERN plans to shut down the LHC for a long time in 2019, during which time it is being considered to introduce a new cable to the injector as part of the LHC upgrade system. However, due to the pile of used cables that have accumulated so far, we are in a situation where we do not have enough space to install new cables.

Sebastian Evlad, head of CERN's equipment repair project, said, 'Of course, when introducing new equipment, it's ideal to get rid of old cables that are no longer in use, but that's not the case. That's why old cables are now in the way and it's no longer possible to add new ones. '

Mr. Evrad's group is proceeding with the identification work of unnecessary cables, and has already completed the identification of 3000 out of 9,000 cables. However, in the case of PS booster cable, for example, the length of one cable is tremendous 50m to connect from the injector to CERN's Geneva base, the scale of the cable is an order of magnitude, and the removal work is not straightforward. Therefore, this year, the main work is to identify and cut the cable, and it seems that the work to remove the unnecessary cable itself will be done from next year onwards.



CERN has renewed its recognition that tidying up cables is an unavoidable task, and has set out to build a database that records all cable features, functions, and locations. Is not 100% reliable. ' In fact, after a few weeks of cable identification and database creation, we found that 2% of the cables we expected to no longer be in use were actually in operation. The work may be more difficult than you might think.

According to Mr. Evlad, cable replacement work is planned to be done during the regular inspection work of the LHC, but all the work is expected to be completed in 2020.


By Pietro Zanarini

in Note,   Hardware,   Science, Posted by darkhorse_log