Happy
Birthday
50
CERN
Herwig Schopper
Talk to CERN Students, 13 August 2004
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
Foundation of CERN
Two initiatives in parallel:
1.physicists:
join European forces to be competitive with US,
in particular for large facilities
E.Amaldi, P.Auger, L.Kovarski, F.Perrin
1950 report by Kovarski: establish intergovernmental
centre, „essentially scientific“
2. Political initiative: European Movement
European Cultural Conference,
Lausanne 8-12 December 1949
bring Europeans together after war
170 people from 22 countries
Ministers, senators, member of parliaments,others
D. de Rougemont (Suiss Writer), R.Dautry ( F Minister), *
Talk to CERN Students, 13 August 2004
The two initiatives combined at 5. General Conference of
UNESCO in Florence, June 1950
-Rabi’s Resolution 7 June 1950 addressed to DG UNESCO
could 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
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
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
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
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
CERN became model
for other organisations
in Europe ESO, EMBL
Joint Institute for Nuclear Research JINR
Established for Warsaw pact states in March 1956
First organisation following CERN
Close cooperation with CERN
important 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 Laboratory
near Amman, Jordan
Intergovernmental 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
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
Examples of Confidence building
CERN – IHEP (Soviet Union) agreement in 1968
became model for IHEP-USA agreement
and later model for USA- Soviet union agreement (Breshnev-Ford)
(Mirabelle staff, 1. Strike on SU territory)
Disarmament meeting at Geneva in 1980ies
when 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
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
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
CERN crossing the Swiss-French Border
LEP/LHC
PS/ISR
SPC
Talk to CERN Students, 13 August 2004
Memberstates of CERN
Von 12 zu 20 Mitgliedsstaaten
+ Associates USA, Russland, Japan, Indien, Israel,........
Talk to CERN Students, 13 August 2004
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
Users in whole World
Talk to CERN Students, 13 August 2004
Domains of Success
Accelerators and Storage Rings
Detectors, Information Technology
Large Experimental Facilities
(“Experiments”) Coordination
Scientific Results
Talk to CERN Students, 13 August 2004
Why race to higher energies and
hence big facilities?
1.The smaller constituents of matter are,
the stronger they are bound together
Heisenberg 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
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 several Radiation 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
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
John Adams with Vodka-Bottle from JINR
to empty when PS more than 10 GeV
PS reached 24 GeV on 24 November 1959
Talk to CERN Students, 13 August 2004
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
Layout of
ISR
Talk to CERN Students, 13 August 2004
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
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
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 DGs
only 1981 full unification of lab
-started operation 1976
Important Extension of Site to France
Talk to CERN Students, 13 August 2004
John Adams and Willibald Jentschke in
SPS Tunnel 1973
Talk to CERN Students, 13 August 2004
Super-Proton Synchrotron SPS
Powerful secondary beams
two new experimental areas, West and Nord (in France)
Muon-, Pion-, Neutrino – beams
Polarised beams and Targets
Heavy- Ion Acceleration AU- nuclei
Investigate 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
*
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
p – p collider
Disadvantage: complicated events
Protons not elementary, contain 3 Quarks + Gluonen
Quarks
Gluons
Advantage: Protons easy to accelerate
limited by magnet field strength and radius
e+ e- collider
Advantage: give clean events, high event rates
e+ 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
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
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
Talk to CERN Students, 13 August 2004
End 2000
CERN Budget
Talk to CERN Students, 13 August 2004
LEP
Positions
Talk to CERN Students, 13 August 2004
Top secret
Water in LEP Tunnel
Talk to CERN Students, 13 August 2004
Mrs.Thatcher at CERN 1983
Talk to CERN Students, 13 August 2004
Paul Johannes II at CERN
Talk to CERN Students, 13 August 2004
Talk to CERN Students, 13 August 2004
LEP Groundbreaking 1983
Presidents Aubert (CH) and Mitterand (F)
Talk to CERN Students, 13 August 2004
LEP Construction
Conventional machine ??
new Technologies (examples)
o about 3000 bending magnets (iron sheets with concrete in
between), mass quality control, installation
o highfrequency accelerating cavities,
first copper, later superconducting Nb
o new Getter-Pumps, extreme highvacuum in 27 km
o 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
LEP Tides
Talk to CERN Students, 13 August 2004
LEP Tunnel
Talk to CERN Students, 13 August 2004
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
Detectors, Data Handling
Bubble chambers Gargamelle, BEBC,...
Develop technology of superconducting magnets
Multiwire chambers (G. Charpak Nobelpreis)
many applications, customs
„Calorimeter“ Sampling Total-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
WWW developed for LEP - Experiments
Talk to CERN Students, 13 August 2004
Large „Experiments“
Not „Experiment“, project in itself
Management 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
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
CMS
LHCB
ATLAS
ALICE
Talk to CERN Students, 13 August 2004
coin
Scientific Success
Progress in Science by:
1. Spectacular Discoveries
2. Tedious work in detail
3. Missed opportunities
All equally important!
Talk to CERN Students, 13 August 2004
Some (most important?) questions
of Particle Physics
1.Elementary building blocks of Matter?
Quarks, Leptons (charged, Neutrinos)
Supersymmetric particles, other ?
What determines Masses?
2.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
Periodic Systematics of Elementary Particles
Strong force
Charges:
Electrical: +2/3
-1/3
Weak
:
flavour in columns
Strong :
colour
No Strong force
0
-1
Talk to CERN Students, 13 August 2004
Vector Bosons (Spin 1)
Carrier of Forces by exchange
Interaction
Electromagnetic
Boson
Discovery
Photon
Photoeffect
Compton effect
no charge
Strong
Gluon
colour
Weak
W+, WZ
DESY 1976
CERN 1983
weak
charge
Photons do not interact
Gluons interact
W and Z interact
Talk to CERN Students, 13 August 2004
New Paradigma
• Since Democritos, Galilei, Newton:
External building blocks with forces between them explain
phenomena in nature
Only building blocks changed during last 300 years
(molecules, atoms, nuclei, protons and neutrons, quarks and leptons)
Eternal change by different arrangements of blocks
• Present most fundamental recognition:
Symmetries and their (spontaneous) breaking
are basis of understanding of Nature
No undestructible building blocks (Newton)
From Democritos to Plato?
Talk to CERN Students, 13 August 2004
Spectacular Successes of CERN
Large transvers momenta at ISR 1972
Indication of partons inside nucleon
Neutral currents (Z) of weak interaction
Gargamelle 1973 (Lagarigue)
W and Z with SPPS,
UA1 und UA2 1983 (Rubbia, van der Meer)
Gluon discovered at DESY
Talk to CERN Students, 13 August 2004
Pion Production with large transverse
momenta at ISR
Indication of
pointlike
partons
Talk to CERN Students, 13 August 2004
Gargamelle Heavy Liquid Chamber
Filled with
16 tons of
Freon
Talk to CERN Students, 13 August 2004
Neutral
Currents
Gargamelle 1973
Elastic Scattering
+ e   + e
Elektron  Bremsstrahlungcascade
Talk to CERN Students, 13 August 2004

UA 1 Detektor
„Hermetic“ Detector
Talk to CERN Students, 13 August 2004
UA1 Z e- + e+
Talk to CERN Students, 13 August 2004
Z – event in OPAL at LEP
Talk to CERN Students, 13 August 2004
Discovery of W and Z Press Conference 1983
Talk to CERN Students, 13 August 2004
visa
‚Work in detail‘
Impossible to mention here all relevant results of CERN
Nucleon-Structure (with polarisation)
Neutrino –Scattering (except neutral currents)
CP-Violation (LEAR)
K and B Oscillations
Quark-Gluon –Plasma
Exotice Atoms and nuclei, Anti-hydrogen
g –2 of Muon
Talk to CERN Students, 13 August 2004
Missed Opportunities
Second Neutrino PS 1961
J/ at ISR 1972
 at ISR 1972
BNL
1974 BNL,SLAC
FermiLab 1977
Experience, hard work and
perseverance do not suffice
A little bit of luck
is also needed !!
Talk to CERN Students, 13 August 2004
LEP Results
No Sensations (TOP, SUSY, Higgs)
But fundamental results from detailed work
Weak Interactions
• Precision measurements
turned HEP into Precision Physics (< 0.5 %)
• Standard-Modell is renormalisable
Fieldtheorie
Radiation corrections (cp. Lambshift) (TOP - Quark),
• 3 Kinds of Neutrinos
• Coupling W-Z-Z
Talk to CERN Students, 13 August 2004
Position of Maximum
gives
Linenwidth and Hight give
No. of Neutrino kinds
(Nν = 2.985 ± 0.008)
Talk to CERN Students, 13 August 2004
Standard
Model with
Precision < 1%
confirmed
Talk to CERN Students, 13 August 2004
Existence of
coupling
between W-Z
Talk to CERN Students, 13 August 2004
Strong and other Interactions
1. 3- and 4 – Jet Physics
Quark-Physics , Gluon -Gluon – coupling
2. Running coupling constant S
(Quark –Confinement  Asymptotic freedom)
3. Limit for Higgs-Mass
(discovery with LHC)
4. Indication for Supersymmetry
Gand Unification ?
Talk to CERN Students, 13 August 2004
Talk to CERN Students, 13 August 2004
Talk to CERN Students, 13 August 2004
Talk to CERN Students, 13 August 2004
LEPmortHS
LEP Fest October 2000
Talk to CERN Students, 13 August 2004
The Secret of Success
 scientific quality and competence count
(no „by-in“)

no national or other quota
for employment of personel
or adjudication of industrial contracts (no „just retour“)

no secrecy, cooperation in spite of competition

no discrimination of nationality, race, origin, religion
*
 ambition to be at frontier of world excellence, in spite of high risks
 Memberstates in favour of pragmatic solutions
avoiding purely political aspects
Talk to CERN Students, 13 August 2004
Future of CERN
Guaranted with LHC
Fundamental discoveries likely and needed for HEP
CERN excellent Laboratory
avoid bureaucratisation, too little staff
Many difficulties not surprising
similar as with LEP
e.g. bell shaped spending profile with constant
Finances will not be end of HEP,
but long time scales are worrisome!!
Interest of young scientists !!!
Talk to CERN Students, 13 August 2004
Talk to CERN Students, 13 August 2004