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LS2 Report: East Area version 2.0


Upgrade of magnets in Hall 867 - Magnets to be installed B157
Half of the magnets from the East Area are renovated in Building 867, in Prévessin (as seen in the picture), the other half are currently being manufactured in several European countries (Image: CERN)

The major work to renovate the East Area of the Proton Synchrotron (PS), which began in 2018, will continue throughout LS2. This transformation of one of CERN’s oldest installations into a modern experiment area at the cutting edge of technology will take several years.

The civil engineering work, which mainly involves restoring the outer shell and roof of Building 157 (the East Area), should be completed within a few months. The building’s energy efficiency will be greatly improved, a prospect that won the SMB department and the project a major grant from the Office cantonal de l’énergie de Genève (OCEN).

But inside the building, the metamorphosis has only just begun. No fewer than 250 metres of beam lines supplying the CLOUD, CHARM and IRRAD experiments and the associated experiment areas must be renovated. “All the power converters, which use technology dating from the 1950s, will be replaced. The new converters, developed at CERN, will supply the magnets on a cyclical basis, with an energy recovery stage between each cycle. Electricity consumption should thereby fall from 11 GWh/year to around 0.6 GWh/year,” explains Sébastien Evrard, leader of the PS East Experiment Area renovation project. “As for the magnets, half of them will be renovated and the other half are currently being manufactured in several European countries.” Some 64 power converters and 60 magnets are concerned.

The beam lines will be arranged in a new configuration, with flexible optics, and new beam profile control monitors will be installed in order to carry out very precise measurements on the secondary beams. These scintillating fibre detectors have been developed at CERN by the Beam Instrumentation group to replace the less powerful delay wire chambers that were usually used in the past.

The renovation of the beam lines will begin in August with the installation of the new extraction line from the PS. By then, the experiment area will have been fully dismantled: more than 250 km of cables are yet to be extracted (50 km have already been removed), as well as 2000 tonnes of shielding blocks (of the 5000 tonnes present in the East Area).

This project, which is being steered by the EN/EA group, involves many other CERN groups from the EN, BE, TE, SMB, EP, HSE, IT, IPT and FAP departments, as well as external institutes, notably the University of Patras (Greece), the Joint Institute for Nuclear Research (JINR, Russia) and the Pakistan Atomic Energy Commission (PAEC). “Sincere thanks are due to all the teams for their tremendous commitment!” says Sébastien Evrard.

The recommissioning of the East Area is planned for the end of 2020, with physics scheduled to start again in spring 2021. This historic experiment area has served physics for more than half a century and, thanks to the modernisation work under way, will continue to do so for many more years to come.


For more information, see this article, published in June 2018.