CERN Courier

Balance of power A prototype storage cavity for LEP's copper radio-frequency system, photographed in 1980. The largest electron-positron collider ever built, LEP came of age at a time when particle physics had grown to a planetary scale. Credit: CERN Once

Missing energy has long served as a clue to unseen physics. In December 1930, Wolfgang Pauli suggested a "desperate remedy" to explain the continuous spectrum of beta-decay electrons: an undetected, neutral state that accompanied the electron, carrying of

Particle accelerators are complex engineering marvels, with thousands of components working in concert. Magnets bend, focus and shape particle beams, while radio-frequency cavities accelerate them and keep the bunches dense. Feedback systems stabilise the

On 22 May, at a dedicated session in Budapest, the CERN Council updated the European Strategy for Particle Physics. The update confirms the full exploitation of the scientific potential of the LHC, through the completion of its high-luminosity upgrade (Hi

On 27 June 2026, proton beams circulated through the LHC for the final time before the machine entered its third Long Shutdown (LS3). After four years of operation, the world's highest-energy particle accelerator now begins an ambitious programme of upgra

Steep climb Monthly submissions to arXiv since its launch in 1991, climbing past 30,000 for the first time in early 2026. Credit: arXiv Authors who submit a paper containing unchecked output from a large language model (LLM) will risk a year's suspension

The CMS collaboration reported an excess of top-antitop pairs in a new decay channel, consistent with the formation of a fleeting quasi-bound state.

The European Strategy has recommended the FCC-ee as CERN's next flagship collider. The case for it, Alain Blondel argues, rests on 50 years of inventions and discoveries.

In parallel, theorists have published an updated Standard Model prediction based purely on lattice QCD.

The signal could be caused by a quasi-bound top-antitop meson commonly called "toponium".