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Happy Birthday CERN

In this talk, Herwig Schopper discusses the foundation of CERN, its objectives, challenges faced, and its role as a model for other European organizations. He emphasizes the importance of scientific cooperation and unity in achieving peace and progress.

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Happy Birthday CERN

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  1. Happy Birthday CERN 50 Happy Birthday Herwig Schopper Talk to CERN Students, 13 August 2004

  2. Council argued that CERN should make history,not talk or write about it * But CERN is such a unique European success (1. European organisation) that one should learn from 50 years of experience I shall talk about History Successes and Failures Talk to CERN Students, 13 August 2004

  3. Foundation of CERN • Two initiatives in parallel: • 1.physicists:join European forces to be competitive with US, in particular for large facilitiesE.Amaldi, P.Auger, L.Kovarski, F.Perrin1950 report by Kovarski: establish intergovernmental centre, „essentially scientific“ • 2. Political initiative: European Movement • European Cultural Conference, Lausanne 8-12 December 1949bring Europeans togetherafter war • 170 people from 22 countriesMinisters, senators, member of parliaments,othersD. de Rougemont (Suiss Writer), R.Dautry ( F Minister), * Talk to CERN Students, 13 August 2004

  4. The two initiatives combined at 5. General Conference of UNESCO in Florence, June 1950 • Rabi’s Resolution 7 June 1950addressed to DG UNESCOcould be considered as‘conception’ of CERN (or real birth??) • At CERN 30. Anniversary 1984 • Rabi’s speech: CERN peaceful compensation for building bomb • “CERN was founded less then ten years after the bomb was made. I feel that the existence of the bomb …had a large part in making CERN possible. ....Europe had been the scene of violent wars..for 200 years. Now we have something new in the founding of CERN” • “I hope that the scientists at CERN will remember that they have other duties than exploring further into particle physics. They represent the combination of centuries of investigation and study… to show the power of human spirit. So I appeal to them not to consider themselves as technicians …but .. as guardians of this flame of European unity so that Europe can help preserve the peace of the world.” Talk to CERN Students, 13 August 2004

  5. Agreement to constitute “Council”signed on 15 February 1952 by 11 countries Approval of Convention 1 July 1953, signed until December 1953 by 12 States Subsequent submission of letters of ratification to UNESCO DG Convention comes into force if ratified by at least 7 States: on 29 September 1954 (Birth!!?) CERN became intergovernmental organisation who knows what CERN stands for? Conseil Européen pour la Recherche Nucléaire « N » is problem Talk to CERN Students, 13 August 2004

  6. Objectives of CERN Promote science and technology (later training)to make Europe competitive Bring nations together first in Europe, later worldwide CERN only lab with both objectives (now also SESAME) CERN became first European Organisation Expectations were met in excellent way Talk to CERN Students, 13 August 2004

  7. Some Problems at Foundation Difficulties forgotten today, but start was not easy 1. Choice of site :Proposals::Geneva (CH), Copenhagen (DK), Arnhem (NL), Longjumeau (Paris) ‚…delegates had clearly been officially briefed to make stiff fight., scientific prestige …was clearly rated very high,… expectation of ..appreciable .. ‘financial gain’ Final decision at 3. Council meeting at Amsterdam October 1952 Geneva:small country, neutrality, nice living conditions Talk to CERN Students, 13 August 2004

  8. 2. National Financial contributions Proportional to income and wealth, but how to asses it? GNP or GNP per capita? Sweden and CH against GNP/capita (since their GNP/capita 50% higher than UK und F !) Italy and Yugoslavia in favour ‚...endless and confused discussion..’ Ben Lockspeiser (Council President) exploded, fed up with ‘shameful horsedealing’ ‘Offended, a Swedish Delegate broke down and wept openly’ Final solution: GNP with limit of 25 % maximum contribution Talk to CERN Students, 13 August 2004

  9. CERN became model for other organisationsin Europe ESO, EMBL Joint Institute for Nuclear Research JINR Established for Warsaw pact states in March 1956 First organisation following CERN Close cooperation with CERNimportant bridge between West and East during cold war New role after disappearance of Soviet union New Charter in 1992 Now 18 Member States SESAME Synchrotronradiation Laboratorynear Amman, JordanIntergovernmental organisation like CERN, Estbalished by UNESCO April 2004 according to CERN model Presently 7 Members (Bahrain, Egypt, Israel, Jordan, Palistan, Palestine, Turkey,.....Iran, Kuwait, Yemen, UAE) Talk to CERN Students, 13 August 2004

  10. Basic Physics using large facilities is excellent tool for ‚Science for Peace‘ • Laws of physics are valid everywhere • No secrecy in basic science (neither industrial nor military) • Large facilities (accelerators, reactors, detectors, telescopes, etc) need scientific, administrative and political cooperation (at highest level) • Cooperation creates confidence between people from different nationalities, religions, cultures, mentalities, political systems • Physicists in basic science give priority to science* instead to money Money has only secondary importance, not main motivation, profession is hobby Talk to CERN Students, 13 August 2004

  11. Examples of Confidence building • CERN – IHEP (Soviet Union) agreement in 1968became model for IHEP-USA agreementand later model for USA- Soviet union agreement(Breshnev-Ford) (Mirabelle staff, 1. Strike on SU territory) • Disarmament meeting at Geneva in 1980ieswhen in deadlock private meeting (USA,USSR) at CERN unblocked it(Trivelpiece asked for lunch) • Meeting with Ambassadors of Disarmament Conference‘Avoid collisions between countries, CERN does better’ Talk to CERN Students, 13 August 2004

  12. Science radiates into politics • CERN-JINR,Dubna: only link East-West Germany • L3 chinese from Mainland and Taiwan • SESAME: Israel -Palestine – Iran Help individuals who have of political, racial or religious problems Orlov (from Sowjetunion to CERN, talk to Petrosyansk) Okun (in SPC, not allowed to come, talk to Chuvilov) Hadizadeh (arrested in Iran, letter to Minister and Chatami, could come to SESAME meetings, now in USA) Help developing countries Talk to CERN Students, 13 August 2004

  13. In time where relations between some nations are sometimes characterised by hatred and violence it is gratifying that scientists, administrators and politicians are prepared to sit around the same table to discuss scientific projects Small light in dark times Talk to CERN Students, 13 August 2004

  14. CERN crossing the Swiss-French Border LEP/LHC SPC PS/ISR Talk to CERN Students, 13 August 2004

  15. Memberstates of CERN Von 12 zu 20 Mitgliedsstaaten + Associates USA, Russland, Japan, Indien, Israel,........ Talk to CERN Students, 13 August 2004

  16. Working Style of CERN Tasks shared between CERN – Users • CERN builds and operates facilities, coordinates exploitation (Technical Competence)“Service Station” • Users come from Universities, national Labs, etc. (about 6000, of which only about 80 from CERN) (Scientific Competence, Rejuvenation) Talk to CERN Students, 13 August 2004

  17. Users in whole World Talk to CERN Students, 13 August 2004

  18. Domains of Success • Accelerators and Storage Rings • Detectors, Information Technology • Large Experimental Facilities (“Experiments”) Coordination • Scientific Results Talk to CERN Students, 13 August 2004

  19. Why race to higher energies and hence big facilities? 1.The smaller constituents of matter are, the stronger they are bound togetherHeisenberg uncertainty p . R ≈ h/2π„Atom smashers“ 2. To produce heavy particles and new states of matter (energy concentrations like after big bang)E = m.c2 Collider Rings Talk to CERN Students, 13 August 2004

  20. Why are detectors so big? • Momentum measurement in magnetic field B p . R ∞ B B limited to several Tesla, ∆R limited to 10 to 100 micron => R must be order of meter for p of several GeV • ‘Calorimeter’ must contain particle shower of severalRadiation length for hadron showers λ about 0.5 m ( ∞ log Energy) => calorimeter length more than a meter But also precision in determining coordinates!!!! Talk to CERN Students, 13 August 2004

  21. Accelerators: First Period of CERN: ‚Copy‘ Machine with highest energy in Europe, ‚copy‘ of BNL machine Proton-Synchrotron PS Protons 28 GeV (circumference 200 m), Main objective at foundation of CERN, Start of operation 1959, workhorse for many years In operation still today, pre-accelerator for all other machines Talk to CERN Students, 13 August 2004

  22. John Adams with Vodka-Bottle from JINRto empty when PS more than 10 GeV PS reached 24 GeV on 24 November 1959 Talk to CERN Students, 13 August 2004

  23. Second Period of CERN: Unique Facility ISR Intersecting Storage Rings Proton-Proton Speicherring„Collider“ Two deformed Magnet - Rings, cross in 8 points, Counter-rotating Proton beams with 31 GeV (up to 60 A). Talk to CERN Students, 13 August 2004

  24. Layout of ISR Talk to CERN Students, 13 August 2004

  25. Fixed Target <=> Collider • Advantage of Colliders: • Car driver knows the effect of head –on collisions • Useful Energy is Center of Mass Energy • ES = 2 x Ekin (kinetic Energy Ekin) • ISR ES = 62 GeV • Particle hitting target at rest ES ~√Ekin • ISR equivalent Energy 2000 GeV! • - Storing beams increases probability of collisions • Disadvantage of Colliders: • No secondary beams of other particles Talk to CERN Students, 13 August 2004

  26. ISR Intersecting Storage Rings • Many Records in the art of accelerator building • Storage time of several weeks once Antiprotons stored for 1000 hours New limit for lifetime of antimatter • New window für physics • ISR was unique in World, • (no successor up to now, only LHC) • 1984 difficult and painful decision to stop it, • ( to find ressources for LEP) Talk to CERN Students, 13 August 2004

  27. Next step:Super-Proton-Synchrotron SPS Proton-Accelerator Energy 400 GeV To be able to compete with American Fermilab 1000 Magnets in Tunnel with about 7 km circumference Failed almost since new sites were proposed in 12 states,but no agreement Solution CERN I und CERN II , 2 DGsonly 1981 full unification of lab -started operation 1976Important Extension of Site to France Talk to CERN Students, 13 August 2004

  28. John Adams and Willibald Jentschke in SPS Tunnel 1973 Talk to CERN Students, 13 August 2004

  29. Super-Proton Synchrotron SPS • Powerful secondary beamstwo new experimental areas, West and Nord (in France) Muon-, Pion-, Neutrino – beamsPolarised beams and Targets • Heavy- Ion Acceleration AU- nucleiInvestigate Quark – Gluon Plasma (first observation ?)* SPS still in operation for fixed target Physics and pre-accelerator for (LEP)/LHC Talk to CERN Students, 13 August 2004

  30. Period of Matter – Antimatter Colliders Particles – Antiparticles in same Ring Protons – Antiprotons in SPS ring 2 x 400 GeV SPPS (third mode of operation of SPS) (proposal Rubbia) ES = 800 GeV Equivalent energy 155 000 GeV , Even today not realisable! But Antiprotons difficult to produce ‚stochastic cooling‘ to homogenise direction and energy (against Liouville‘s Theorem) Maxwell‘s Dämon ? Simon van der Meer (Nobelpreis 1983) Talk to CERN Students, 13 August 2004

  31. p – p collider Disadvantage: complicated events Protons not elementary, contain 3 Quarks + Gluonen Quarks Gluons Advantage: Protons easy to acceleratelimited by magnet field strength and radius e+ e- collider Advantage: give clean events, high event ratese+ and e- have no inner structure Disadvantage: acceleration of electrons very difficult in ring synchrotron radiation losses ~ E4/R Talk to CERN Students, 13 August 2004

  32. LEP Large Electron – Positron Collider Proposal by international community in 70‘ties : Elektron-Positron Collider with 50 to 100 GeV per beam (after succes of ADONE, PEP, DORIS, PETRA, TRISTAN) Look for W and Z, Supersymmetry, top. cost optimisation gives R ~ E2 => circumference about 30 km ?Ring or two colliding lineacs? LEP last circular e+e- facility Such a facility only realisable as World Machine? Could be built at CERN? Talk to CERN Students, 13 August 2004

  33. LEP Approval • Various proposals with „oscillating“ energy and radius • in the late 1970ies • CERN-Council accepts new LEP Design in June 1981 • Tunnel with circumference of 27 km • Conditions: • constant budget (low level) (resign !?) • ‚stripped down LEP’ minimum of components at start • Phases LEP 1 2x 50 GeV LEP 2 2x 100 GeV 3. LHC (Tunnelcircumference) Workshop March 1984 Lausanne • Time is contingency (indeed one year delay) • stop many existing facilities even when still interesting • Groundbreaking 1983 Start up 1989 End 2000 Talk to CERN Students, 13 August 2004

  34. CERN Budget Talk to CERN Students, 13 August 2004

  35. LEP Positions Top secret Talk to CERN Students, 13 August 2004

  36. Water in LEP Tunnel Talk to CERN Students, 13 August 2004

  37. Mrs.Thatcher at CERN 1983 Talk to CERN Students, 13 August 2004

  38. Paul Johannes II at CERN Talk to CERN Students, 13 August 2004

  39. Talk to CERN Students, 13 August 2004

  40. LEP Groundbreaking 1983 Presidents Aubert (CH) and Mitterand (F) Talk to CERN Students, 13 August 2004

  41. LEP Construction • Conventional machine ?? • new Technologies(examples) • about 3000 bending magnets (iron sheets with concrete in between), mass quality control, installation • highfrequency accelerating cavities, first copper, later superconducting Nb • new Getter-Pumps, extreme highvacuum in 27 km • survey procedures (Laser, Satellites) for installation of magnets and other components (Tolerance tenths of mm for distances up to 10 km ) • Not size of tunnel impressive, • But size combined with precision. • Toleranz  circumference = ± 2.8 cm, measured 0.8 cm Talk to CERN Students, 13 August 2004

  42. LEP Tides Talk to CERN Students, 13 August 2004

  43. LEP Tunnel Talk to CERN Students, 13 August 2004

  44. LEP Operation LEP 1:beam energy around 50 GeV for 7 years „Z- Factory“ millions of Z- particles produced (UA1 und UA2 had only handful events for discovery) LEP 2: from 1996 energy increase in steps with SC cavities (Nb massiv and coated) During last months of 2000 achieved 104.5 GeV/beam Energy concentration as 10-10 s after Big Bang of cosmos During 11 years LEP worked excellently Last circular e+e- machine => NLC Talk to CERN Students, 13 August 2004

  45. Detectors, Data Handling Bubble chambersGargamelle, BEBC,... Develop technology of superconducting magnets Multiwire chambers (G. Charpak Nobelpreis)many applications, customs „Calorimeter“SamplingTotal-Absorptionscounter STAC,energy measurement without magnetic field, neutral particles * Crystal counters for Gamma,10000 cristals (application in medicine) Silicon-Strip Detectors a few  Precision Data handling: Collection, reduction, storage, analysis, transfer WWWdeveloped for LEP - Experiments Talk to CERN Students, 13 August 2004

  46. Large „Experiments“ Not „Experiment“, project in itselfManagement success to organise them Institutions on their own: several hundered scientists, administrators,... Components from many Labs in many countries (coordination, fitting together, time schedule) Industry like, but international, no management power! Modell for scientific, technical and financial cooperation („resource committees“) „LEP Model“ continued with LHC experiments 1000 to 2000 scientists Talk to CERN Students, 13 August 2004

  47. LEP Experiments • ALEPH,DELPHI,L3 und OPAL * • International collaborations with hundreds of scientists from countries with different political systems, various traditions, mentalities and religions • Components fabricated in many countries • Cost of each detector 100 to 500 millionen CHF • Hundered to several hundered scientists Talk to CERN Students, 13 August 2004

  48. CMS LHCB ATLAS ALICE coin Talk to CERN Students, 13 August 2004

  49. Scientific Success • Progress in Science by: • Spectacular Discoveries • Tedious work in detail • Missed opportunities • All equally important! Talk to CERN Students, 13 August 2004

  50. Some (most important?) questions of Particle Physics • Elementary building blocks of Matter?Quarks, Leptons (charged, Neutrinos)Supersymmetric particles, other ?What determines Masses? • Which Forces in nature and their properties?Carrier: Photon, Gluon, W, Z (‚heavy Light‘), graviton • Great Unification of Forces ? Talk to CERN Students, 13 August 2004

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