CERN completes civil engineering for ten times more intense LHC accelerator

25 January 2023

In Geneva at CERN, all preliminary work for the construction of the more intense version of the LHC accelerator has been completed. The High Luminosity Large Hadron Collider (HL-LHC) is scheduled to go into operation in 2029.

CERN reports this in a press release. The HL-LHC will deliver up to 10 times more proton collisions per second, allowing particle processes to be studied much more precisely. The HL-LHC is CERN’s most important project this decade, and one of the highest priorities in the 2020 European strategy for particle physics.

Tighter beams 

To this end, several modifications are needed in the 27-kilometer LHC ring, for which new underground rooms and corridors have been built. Their construction has now been completed. Now new superconducting magnets can be built in that will make the beams thinner, and at the same time, systems that allow these beams to collide more effectively in the experiments, called crab cavities.

Work on the infrastructure was approved in 2016 and began in 2018. Much of the equipment will be installed during the LHC’s next multi-year stop after 2026. The high-intensity conversion involves 43 institutes in 19 countries, including member states as well as the U.S., Canada, Japan and China.


The Netherlands makes no direct contributions to improving the LHC accelerator. Through Nikhef, however, the Netherlands is working in three of the four large detector experiments in Geneva. These will all benefit from the more intense collisions in the accelerator.

Nikhef is heavily involved in modifications to the detectors for the more intense beams, and also to the networks that can handle the data tsunami from the HL-LHC.