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Large Hadron Collider is presented to CERN Council

Geneva, 17 December 1993. The CERN1 Council, where the representatives of the 19 Member States of the Organization decide on scientific programmes and financial resources, held its 98th session on 17 December under the chairmanship of Sir William Mitchell (UK).

Large Hadron Collider

In December 1991 CERN's Council delegates agreed unanimously that the Large Hadron Collider (LHC) was the right machine for further significant advance in the field of high energy physics research and for the future of CERN and asked the CERN management to prepare a full technical, scientific and financial proposal for the accelerator for December 1993. Accordingly Prof. Christopher Llewellyn Smith, Director General designate, presented to Council a complete outline of the LHC project.

The Large Hadron Collider (LHC) is an accelerator which will bring protons into head-on collision at higher energies (14 TeV) than ever achieved before to allow scientists to penetrate still further into the structure of matter and recreate the conditions prevailing in the Universe just 10-12 seconds after the "Big Bang" when the temperature was 1016 degrees. The accelerator will produce not only higher energy but also a higher luminosity - the probability of collision between particles - than has been achieved before and it will reveal the behaviour of fundamental particles of matter which has never been studied.

Two detectors, ATLAS and CMS, which will record the interactions created by colliding proton beams at an energy of up to 14 TeV, are already at an advanced stage of development. However the LHC will not be limited to the study of proton-proton collisions, the LHC can also collide heavy ions, such as lead, to produce a total energy of 1148 TeV. A large energy density can be obtained over a wide enough region in these collisions to cause phase transition of nuclear matter into quark-gluon plasma. Studies of such a state of matter are expected to yield important new results. Proton-proton collisions at the LHC will be a copious source of B-mesons. The study of the decay of these mesons will allow physicists a deeper examination of CP-violation and a tailor-made B-physics detector is under development for LHC. At a later stage, proton beams from LHC can also be made to collide with electron beams from LEP opening up another field of research. This wide range of physics possibilities will enable LHC to retain its unique place on the frontiers of physics research well into the next century.

The building of the LHC and its detectors is a challenge to both European scientists and European industry. New projects pose new problems, with solutions at and often beyond the leading edge of contemporary technology. Many companies are already partnering CERN in research and development to build the LHC machine and its particle detectors. European industry faces stimulating challenges in many fields, for example, superconductivity, ultra high vacuum, ultra low temperatures, unprecedented data rates. The mastery of these techniques will enhance its competitiveness in the short term and also lead to longer term developments.

Prof. Llewellyn Smith referred to the very positive conclusions of the external review committee chaired by Dr R. Aymar, Director of Sciences de la Matire from the French Commission d'Energie Atomique (CEA). This committee was asked to study the technical feasibility of the LHC project and their main findings were that :

  • The machine design, providing two beams of 7 TeV with a luminosity of 1034 cm-2s-1 is quite realistic
  • LHC's two-in-one magnets, with superfluid helium cooling are the only appropriate options to achieve performance with lowest investment cost
  • There is no doubt that a dipole field of 8.65 Tesla can be achieved
  • The cryogenic system, even if large and complicated, is completely feasible
  • The cost estimate for magnet and cryogenic systems is accurate and there is enough potential cost savings to avoid need of contingency
  • The project should be approved rapidly

Prof. Llewellyn Smith announced a total machine cost for LHC of 2230 MCHF, in 1993 prices. The major cost attributes are the superconducting magnets and the cryogenics, which account for more than 75% of the total cost. This cost estimate includes all material costs incurred for the components, related tooling and test facilities, for the utilities and for the additional civil engineering necessary to complete the LHC in the LEP tunnel, ready for operation. Assuming that the LHC-decision is made in 1994, the construction of the machine will start in 1995 and the collider would start to be commissioned in the year 2002. The main effort during the construction phase is concentrated in the four year period 1998 to 2001.

Prof. Llewellyn Smith paid tribute to the dynamic work of Prof. Carlo Rubbia and Dr Giorgio Brianti and the commitment of the CERN staff. Thanks to their efforts the scientific justification and technical feasibility of LHC are now fully established. Prof. Llewellyn Smith underlined that the LHC project was one part of a fully integrated 10-year plan for the scientific programmes of the Laboratory during the years 1995-2005. He gave a full analysis of the financial resources, manpower needs and funding proiiles. He mentioned the possibility of additional income from Member States and, following the cancellation of the Super Conducting Super Collider (SSC) in the United States, contributions from non-Member States. Prof. Llewellyn Smith said CERN would welcome the valuable intellectual input from non-Member State physicists to the LHC programme, but underlined that participation should be linked with a financial contribution to the project. In conclusion, he asked the Member States to approve the LHC project in 1994 and to work towards an agreement on funding and a construction timetable.

Summary of Council discussion

Prof. Sir William Mitchell, President of Council, after thanking Prof. Llewellyn Smith for his presentation summed up the conclusions of Council and its consultative bodies.

Council confirmed its belief as stated in its December 1991 resolution that the LHC was the right next machine for particle physics and for CERN. Council congratulates CERN, and all the staff involved, on the thorough account of the LHC project and experiments, which has been presented. Council was impressed by the scientific case and the economical way of achieving the LHC by the considerable utilization of previous investments. Council endorsed the overall programme strategy of CERN covering 10 years and noted that a number of first class activities had been curtailed in that strategy for financial reasons.

Council wishes to move during the first half of 1994 to a decision and wishes to see the LHC as part of the basic programme of the Laboratory.

It is conscious of, and welcomes, the world interest in the project and encourages CERN to report back in March on the modes of involvement of non-Member States. Council wishes that such involvement should be on the understanding that usage on a significant scale must involve the provision of resources to suit both CERN and the non-Member States concerned. These and other options of funding will be presented for further discussion in March 1994.

Director General's Report

CERN's Director General, Prof. Carlo Rubbia, gave a detailed overview of the scientific activities of the Laboratory in 1993. Three highlights from this talk should be mentioned. The Large Electron Positron Collider (LEP) has performed excellently and this year significantly passed its design luminosity. Over 8 million Zo events have now been recorded by the four LEP detectors. The Director General highlighted the importance of two new neutrino experiments NOMAD and CHORUS. The aim of these experiments is to establish whether neutrinos have mass. If this is proved it will be a major discovery with profound implications for our understanding of the missing mass of the universe. He also outlined the enormous advances that have been made in international computer networking. Due to the advanced computer networking established in the Laboratory more information now flows in and out of CERN than in any individual European country. The Laboratory has established itself as a leader in information networking around the world.

Budget for 1994

The budget of the Organization proposed by the CERN Management of 924.1 MCHF (at 1993 prices) was approved by Council. As for indexation for compensation for the variation of the cost of living, the global index has been fixed at 1.7% with 1.6% for the overall personnel index, and 1.8% for materials. CERN Pensions were indexed for cost of living increases at 3%.

Spanish contribution

Council was informed that there had been positive discussions about the Spanish debt and contribution level at a meeting in Madrid of the three ministers involved and the President of Council, the Director General, together with Prof. Curien and Prof. Llewellyn Smith. Spain has undertaken to pay its debt as soon as possible and further discussions will be held in the new year on possible temporary alleviation of the contribution level.

Purchasing policy

A working group under the chairmanship of Dr Gigliarelli Fiumi was set up in September 1992 to study CERN's purchasing policy and procedures. The outcome of the working group's examination was presented at Council. It was agreed that a substantial improvement of the balance of return coefficients - the ratio between a Member State's share of all purchases of goods and its percentage contribution to the budget - should be obtained for purchases among all CERN's Member States.

Industrial and technological returns from CERN to firms in Member States are among the priorities of the Organisation and it is in the interest of CERN and its Member States to achieve a balanced distribution of industrial and technological returns. The working group recommendations covered a wide range of improvements to the purchasing policy which will have effect from January 1994 for a 3-year transitional period.

To ensure a more equal distribution of contracts, the working group decided that if the lowest bid for a CERN contract is from a firm in a Member State with a well balanced return coefficient, CERN will enter into negotiations with the two lowest bidders in Member States with poorly balanced return coefficients provided that their tenders fall within 20% of that of the lowest bidder. The working group also encouraged Member States to strengthen industrial liaison with CERN, wherever possible through the establishment of industrial liaison offices. CERN management should also devote special attention to industrial liaison with those Member States with poorly balanced industrial return coefficient.

Thanks to President of Council and Director General

With resounding applause Council delegates expressed their gratitude to Carlo Rubbia and Bill Mitchell at the end of their mandates as Director General and President of Council.


Dr Hermann Strub (Germany) was elected Vice-President of Council for the period of one year.

Dr. Bjorn Brandt was re-elected as Chairman of the Finance Committee for a period of one year.


Dr. Günter E. Wolf, DESY, Hamburg was re-elected as chairman of the Scientific Policy Committee (SPC) for a period of one year.


Three new members were elected to the Scientific Policy Committee for a period of three years as from 1 January 1994 : Prof. Hans J. Specht, Prof. Andrzeij Wroblewski. and Prof. Abraham Seiden.


Appointments to senior posts

Council approved the proposed appointment of Prof. Gabriele Veneziano as leader of the Theory division as from from 1 July 1994.

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.