CERN makes public the first data from LHC experiments

CERN has this week launched an Open Data Portal, making data from Large Hadron Collider (LHC) experiments openly available to all for the first time.

Experiments at the LHC at CERN are addressing some of the most fundamental questions about the origin, evolution and composition of our universe.  Many members of Imperial College London's High Energy Physics group have been working on the mission to find new particles, detect the Higgs boson particle, and explore some of the mysteries of the universe, such as where mass comes from and what constitutes dark matter.

The CMS data made available this week were originally collected in 2010 during the first LHC run.

The newly available data come from real collision events produced at the Compact Muon Solenoid (CMS) particle detector experiment, one of the two general purpose experiments at the LHC. It is expected that they will be of high value for the research community, and will also be used for education purposes.

"Launching the CERN Open Data Portal is an important step for our organization. Data from the LHC programme are among the most precious assets of the LHC experiments, that today we start sharing openly with the world. We hope these open data will support and inspire the global research community, including students and citizen scientists," said CERN Director General Rolf Heuer.

Dr David Colling from the Department of Physics at Imperial is one of those behind the project to make the LHC’s data openly available. He said: “We’re really pleased to be able to share these data with the public for the first time and we think ours is the first particle physics experiment to make its data available like this. Publicly funded data are a public good, and it’s right that people can access the data that we have been able to generate thanks to their funding.”

The principle of openness is enshrined in CERN's founding convention, and all LHC publications have been published Open Access, free for all to read and re-use. Widening the scope, the LHC collaborations recently approved Open Data policies and will release collision data over the coming years.

Adam Huffman from Imperial’s Department of Physics is part of a team that has been working on the technical infrastructure that has made it possible to share the data. He said: “It’s great that everyone from school children to the lay public to particle physicists is going to be able to look at what the LHC has produced. For the physics community, sharing these data is particularly good news because it ensures that experiments can be re-run in the future and findings can be validated. If we have a community of people both inside and outside CERN working with the data, they will still be usable in 20 years’ time. Making the data available to all means it can take on a life of its own.”

The first high-level and analysable collision data openly released were originally collected in 2010 during the first LHC run. This data set is now publicly available on the CERN Open Data Portal. Open source software to read and analyse the data is also available, together with the corresponding documentation. The CMS collaboration is committed to releasing its data three years after collection, after they have been thoroughly studied by the collaboration.

In parallel, the CERN Open Data Portal gives access to additional data sets from the ALICE, ATLAS, CMS and LHCb collaborations, which have been specifically prepared for educational purposes, such as the international masterclasses in particle physics benefiting over 10,000 secondary school students every year. These resources are accompanied by visualisation tools.

All data on OpenData.cern.ch are shared under a Creative Commons public domain dedication; data and software are assigned unique DOI identifiers to make them citable in scientific articles; and software is released under open source licenses. The CERN Open Data Portal is built on the open-source Invenio Digital Library software, which powers other CERN Open Science tools and initiatives.