05 Novembre 2003 1

Dr. Yannis PAPAPHILIPPOUACCELERATOR AND BEAMS Department

Welcome to CERN!

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What is CERN?A short historical overview

• 1949-1950: First ideas for creating a European laboratory in physics

• 1952: Foundation of the European Council for nuclear Research (Conseil Européenpour la Recherche Nucléaire-CERN) under the auspices of UNESCO

• July 1953: During the 6th session of the council in Paris, a convention was signed establishing the European Organization for Nuclear Research

• 1954: Official ratification of the convention from the first 12 member states (Belgium, Denmark, France, Germany, Greece, Holland, Italy, Norway, Sweden, Switzerland, UK and Yugoslavia)

On June 10 1955, Felix Bloch, CERN’s first Director General, places the founding stone on the new laboratory site, watched by Max Petitpierre, than President of the Swiss Confederation

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Who works at CERN

• 20 European member states:Austria, Belgium, Bulgaria, Czech RP, Denmark, Finland, France, Germany, Greece, Holland, Hungary, Italy, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and UK

• Observer states and organizations: European Council, India, Israel, Japan, Russia, Turkey, UNESCO and USA

• More than 80 non-member states collaborate in CERN’s programs

• 2500 staff members• More than 7000 users (500

Universities and laboratories)• Annual budget ~ 1000 MCHF

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Location of CERN

Geneva Airport LHC accelerator

Main CERN site (Meyrin)

SPS machine

Second CERN site (Prevessin)

French-Suisse borders

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CERN’s mission

Design and construction of accelerators and detectorsfor studying the physics of elementary particles

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The Large Hadron Collider (LHC) is the most powerful accelerator ever built to study the properties of elementary particles

• Four gigantic underground tunnels with huge detectors

• Protons (and ions) will get accelerated to the highest energy ever achieved

• The most intense particle beams will be collided in the four experimental points

• Magnets operate in a temperature lower than the one of space

Large Hadron Collider - LHC

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LHC will start commissioning at the end of 2007 and will certainly change our view about the universe

LHC - A view from the tunnel

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Building the LHC

Circumference of ~27km, 100 meters below the earth’s surface

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CMS Experiment

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Why do we need accelerators?

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Methods of particle physics

3) Detection of the produced particles with Detectors

1) Generation of very energetic particles (accelerators)

2) Particle collisions(conditions of the Big Bang)

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Quarks (Gell-Mann) 1964 Periodic system of fundamental particles

Proton

Constituents of matter

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Four fundamental forces

Type RELATIVE INTENSITY OF

FORCES

Particle exchanged(field quantum) Occurs in:

Electro-magnetic force

Weak force

Gravitation

~ 10-3

~ 10-5

~ 10-38

Bosons Z0,W+, W-

(heavy)

Photons (no mass)

Gluons (no mass)

Gravitons?

ElectricityAtomic shellSun -Radioactive β decayKeeping our feet on the ground

Strong force ~ 1 Atomic nucleus

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A unique force?

Important discoveries at CERN:– Neutral currents (1973)

– Bosons W&Z (C. Rubbia, S. Van der Meer 1983)

– Confirmation of the existence of 3 neutrino families (1989)

S. Weinberg, A. Salam, S. Glashow :Unification of the electromagnetic and weak interaction

J. C. Maxwell (19th

century):Unification of the magnetic and electric force

LHC?

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What is the Universe made of?

96% of the Universe constituents are unknown!!!

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The big questions

Why three generations?

More types of particles? (Dark matter, Supersymmetry)

How particles acquire their masses? (Higgs boson)

LHC will certainly help us solve some of the mysteries

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Detecting the Higgs

We expect to detect 1 Higgs for every 1,000,000,000,000 events

The two proton beam will collide head-on, 800 millions of times per second

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CERN, the Internet and the World Wide Web

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Estimated CPU Capacity at CERN

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

year

K SI

95

Moore’s lawJan 2000:3.5K SI95

LHC experimentsOther experiments

Computing needs at CERN for LHC experiments

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The GRID

The LHC computing GRID is a program financed from the European Union. The purpose is to build the next generation of computing infrastructure

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Industrial applications of CERN developments

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Medical applications of particle physics

Positron Emission Tomography – PET