Latest news from the YETS: keeping up the pace

As we explained in the last edition of the Bulletin (see here), the winter technical stop (otherwise known as the YETS – Year-End Technical Stop) is setting a huge number of experts to work on all of the Laboratory’s accelerators. For the time being, the various maintenance and improvement activities are all on schedule.


Replacing the BHZ62 magnet at the PS Booster. (Photo: Sylvain Fumey.)

At the PS Booster, the task of identifying obsolete cables is almost complete: around 2400 cables have been disconnected and are ready for removal, 400 more are still being analysed, and 66 turned out to still be in use, which underlines the importance of the identification work. Consolidation work is also going well and will soon be completed. Due to an unexpected leak in its vacuum chamber, the BHZ62 magnet has been replaced after 20 years of service.

At the PS, a second cabling campaign has begun in the service tunnels, involving the installation of cables for the TETRA digital radio communication system. The renovation of the bridge cranes at the PS, a process which began 10 years ago, was completed on 22 January with the acceptance test for the final crane. In addition, consolidation work on the cavities and the replacement of certain magnets are proceeding on schedule. The PS should therefore be ready to start powering tests on 13 February.

Identification of obsolete cables at the SPS. (Photo: Sébastien Thoulet.)

At the SPS, 14 of the 16 magnets due for replacement have now been successfully replaced, with the remaining two to follow on 15 February. At the same time, the civil-engineering team is working at Point 5 to prepare for the installation of a new beam dump at this part of the accelerator during the next long shutdown (LS2).

At the LHC, the cryogenic teams are still working flat out to repair the faulty cold-box at Point 8. New water-cooled cables have been installed for the TOTEM experiment. New Roman pots (detectors installed very close to the beam) have been installed near the ATLAS experiment. Meanwhile, the EN-MME teams are taking advantage of the YETS to carry out tomography to check the Sector 6-7 interconnections.

by Anaïs Schaeffer