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CERN Council Gives Go-ahead for Large Hadron Collider

Geneva, 16 December 1994. CERN1 Council, under the presidency of Prof. Hubert Curien, today agreed by consensus to approve the construction of the 14 TeV (1 Tera electron volt, TeV = 1 million million electron volts) Large Hadron Collider (LHC).

Director General Chris Llewellyn Smith said : "Today's decision is a major step for the future of High Energy Physics and CERN. Council's decision represents a 20-year commitment to High Energy Physics research . I believe this to be a unique commitment to fundamental scientific research and I am honoured by this vote of confidence in fundamental science and CERN's scientific capabilities. With this long-term commitment we can now proceed with the challenging task of building the LHC and, with the continued support of CERN's outstanding staff, the Organisation can look forward to taking further important steps in the understanding of matter. We hope to welcome friends from other countries to participate in the LHC, not only financial participation but even more for their very important intellectual contributions. Today's decision has assured a great future for world particle physics and for CERN."

The LHC, a particle accelerator built from high powered superconducting magnets each 14 metres long, will be installed in CERN's existing 27-kilometre circular tunnel constructed for the LEP electron-positron collider. These powerful magnets will hold counter-rotating beams of protons on a steady course around the ring as superconducting accelerating cavities 'kick' them almost to the speed of light at energies higher than have ever been reached in accelerators. When these proton beams collide, at fixed crossing points, their combined energy of motion will produce an intense micro-fireball which will shoot out hundreds of new particles. These flashes of energy will probe the interactions between the tiny quark constituents hidden deep inside the colliding protons and reveal how Nature works at the most fundamental levels.

CERN's Council decided that, to allow CERN's Member States to build the LHC within a constant budget with no financial contributions from non-Member States, the accelerator should be built as a 2-stage project. The first stage being a particle collider with an energy of 10 TeV which would be ready to start experiments in 2004. The research programme on top quark, charge parity (CP) violation and heavy ion physics could be undertaken immediately without appreciable limitations. This machine will already open the exploration of the TeV energy range where the question of the intimate relation between matter and forces can be answered. By 2008 the accelerator will be upgraded by adding magnets to reach a centre of mass energy of 14 TeV, becoming the first instrument which would allow a complete understanding of the origin of mass.

The Member States' representatives also decided on a comprehensive review of the progress of the project before the end of 1997. CERN welcomes international collaboration which benefits all, boosting the progress of science. Several non Member States - USA, Japan, Canada, the Russian Federation, India, Israel - have expressed interest in participating in the scientific programmes opened up by the LHC. If by 1997 it is clear that sufficient financial commitments to the project are forthcoming from non Member States, then it would be possible to re-examine the two stage project and revert to the immediate construction of a 14 TeV accelerator.

Dr John O'Fallon, representing the US Department of Energy, congratulated CERN Council on its decision saying : "The United States' High Energy Physics community has a great interest in the LHC and we invite the Director General and his negotiating team to come to Washington to work on the details of US participation in the LHC." Mr Takahashi, from the Japanese Mission in Geneva, also expressed his happiness on the decision to go ahead with the LHC underlining the intent of the Japanese : "to start examination of the possibilities of Japanese cooperation with CERN on the LHC."

In light of the long-term commitment of the Member States to CERN's scientific programmes Council decided that a zero Cost Variation Index be applied to the Member States' contributions to the CERN budget in the period 1995-1997. It was also decided that planning should proceed on the basis of the assumption that inflation will be 2% and that Member State contributions will be indexed by 1% from 1998 onwards. Council agreed that a new 'double majority' procedure should apply to Finance Committee recommendations to Council relating to the Bannier Procedure, the Annual Budget and the Cost-Variation Index (CVI). This means that a recommendation can only be approved by Council if it has the support of the majority of the Member States and that these Member States collectively contribute 70% of the annual budget of the Organization.

Council noted with gratitude the commitments from France and Switzerland to make voluntary contributions to the LHC project. It was also decided to maintain Germany's contribution to the budget at 22.5% until 31 December 1998.

1. CERN, the European Laboratory for Particle Physics, has its headquarters in Geneva. At present, its Member States are Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, Netherlands, Norway, Poland, Portugal, the Slovak Republic, Spain, Sweden, Switzerland and the United Kingdom. Israel, the Russian Federation, Turkey, Yugoslavia (status suspended after UN embargo, June 1992), the European Commission and Unesco have observer status.