The Large Hadron Collider at CERN, the world’s largest particle accelerator, is again running at full power after an extended winter shutdown. Experiments at the LHC have shared the first images of colliding protons on social media.
The new LHC Run 3 delivers proton collisions at 13.7 GeV, the energy for which the 27-kilometer accelerator was built. The accelerator returned to operation in March, after which the energy was gradually increased.
A stable beam was achieved last weekend. The winter shutdown lasted a month longer than usual to reduce energy costs.
Run 3 will last until the end of 2025. After that, the accelerator will be substantially modified to deliver even more intense beams of protons, the High Luminosity project. According to the plans, the HL-LHC should be in operation by 2028.
Of the four major detectors at CERN, ATLAS, CMS and ALICE have now reported that they have resumed measurements. Nikhef has an important role at CERN in ATLAS, ALICE and LHCb.
Only the LHCb experiment has not yet completed its scientific program. In that detector, after a pressure incident during a test in January, the two halves of the inner VELO detector cannot be brought close enough to the beam for serious measurements. However, tests are possible.
In the incident after the turn of the year, the thin metal casing of the actual detector became deformed. This RF box will be replaced with two spare copies later this year. Nikhef will manufacture two new RF boxes at its workshop in Amsterdam over the next six months.
Such a fraction of a millimeter thin metal shell will be made from a solid block of aluminum using a computer-controlled milling machine. The new boxes will then go to CERN as new spare parts.