How this directory is made.

Every entry links to its sources, and every number on the site can be traced to one: a peer-reviewed paper, a laboratory or collaboration page, or the organization's own publication. Where a figure is an estimate made by a company, it is attributed to that company by name.

Claims that could not be verified are left out rather than approximated. Calculated values, such as the energy of an annihilation or the time to make a quantity at CERN's rate, show their working.

173 entries across experiments, facilities, people, papers, concepts, organizations and applications, plus 20 records, 60 timeline events and 87 glossary terms. Entries are linked to each other automatically wherever one mentions another.

The content was last reviewed in October 2026. Records change; each shows the year it was set.

The full dataset is published as JSON at /api/v1, one endpoint per collection, and summarised for language models at /llms.txt. Use it in research, teaching or products; a link back is appreciated.

The directory is not affiliated with CERN, any experiment listed, or any company. Inclusion is not endorsement. Organizations are described from their own public statements and independent sources.

The animation on the home page is a simulation, not a recording. Charged particles curl in a magnetic field: positrons one way, electrons the other, which is how Carl Anderson identified the positron in 1932. Gamma rays leave no trail and show themselves only when they convert into an electron and a positron. Antiprotons annihilate into sprays of pions, which sometimes decay in flight and leave a kink. Switching to Matter mode reverses the field, so every curl reverses with it.