LS1 report: Cryogenic line goes through scanner

This week, teams have started X-raying the cryogenic line to examine its condition in detail

In spite of the complexity of LS1, with many different activities taking place in parallel and sometimes overlapping, the dashboard shows that work is progressing on schedule. This week, teams have started X-raying the cryogenic line to examine its condition in minute detail.

The LS1 schedule is pretty unfathomable for those who don't work in the tunnels or installations, but if you look down all the columns and stop at the line indicating today’s date, you can see that all of the priority and critical items are bang on time, like a Swiss watch. More specifically: the SMACC project in the LHC is on schedule, with a new testing phase for the interconnections which have already been consolidated; preparations are under way for the cable replacement campaign at Point 1 of the SPS (about 20% of the cables will not be replaced as they are completely unused); and the demineralised water distribution line is back in service, as are the electrical substations for the 400 and 66 kV lines.

Last week, teams were able to begin the campaign to X-ray the cryogenic line in a first sector of the LHC. The experts had noticed leaks all along the line, corresponding to the compensators, which should have been leak-tight. To thoroughly investigate these unwanted anomalies, experts have X-rayed the cryogenic line components over a distance of 6 km.

In the other machines: at the AD, unused power supply cables have been removed from the experiment hall and the amplifiers for the stochastic cooling system have been reconnected; at LEIR, the cabling campaign has been completed; at the PS, the new ventilation systems are being installed; at the PS Booster, the teams have succeeded in moving the entire beam line and other equipment closer to the beam dump. The dump itself, 40 years old and made of carbon steel weighing 200 kg, will be replaced in the coming weeks with a block of copper alloy weighing approximately 2 tonnes.