Today’s Schedule of Your Visit

(1) Presentation about CERN (~ 20 min)-- João BENTO

(2) A short film about CERN and particle physics (~ 10 min)

(3) A visit to CERN facilities (~ 1-2 hours)

05 Novembre 2003 2

European Organization for Nuclear Research

1. What and where is CERN?2. What does CERN do and how does CERN

do it?3. LHC (The Large Hadron Collider) and its 4

experiments4. Particle physics and standard model5. Spin-off of the particle physics (e.g. WWW

was invented at CERN)6. Summary

CERN member states

• Founded in 1954 by 12 countries• Today: 20 member states• More than 7000 users from all over the world• ~1000 MCHF / Year budget

1954: Convention establishing the Organization - original signatures 2004: The 20 member states

4

CERN in NumbersCERN in Numbers

• 2256 staff• ~700 other paid personnel• ~9500 users• Budget (2009) 1100 MCHF

• 2256 staff• ~700 other paid personnel• ~9500 users• Budget (2009) 1100 MCHF

• 20 Member States:20 Member States: Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom.

• 1 Candidate for Accession to Membership of 1 Candidate for Accession to Membership of CERN:CERN: Romania

• 8 Observers to Council:8 Observers to Council: India, Israel, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and Unesco

• 20 Member States:20 Member States: Austria, Belgium, Bulgaria, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, Switzerland and the United Kingdom.

• 1 Candidate for Accession to Membership of 1 Candidate for Accession to Membership of CERN:CERN: Romania

• 8 Observers to Council:8 Observers to Council: India, Israel, Japan, the Russian Federation, the United States of America, Turkey, the European Commission and Unesco

CERN's mission: to build particle accelerators

Accelerator chain at CERN, a complex business

CERN site

LHC accelerator

CERN main site

SPS accelerator

CERN 2nd site

Geneva Airport

CH - F Border

8

The Large Hadron Collider (LHC) will be the most powerful instrument ever built to investigate particles properties.

• Four gigantic underground caverns to host the huge detectors

• The highest energy of any accelerator in the world

• The most intense beams of colliding particles

• It will operate at a temperature colder than outer space

9

The LHC: what it will look like

The LHC will start operation in October 2009. It will certainly change our view of the Universe

10

Preparing the LHC

27 km circumference100 m underground

SM18 MagnetsTest Facility

11

Building the CMS experiment for the LHC

12

Particle accelerator. How it works

Accélération linéaire: - La particule avance tout droit

Le champ électrique (tension) appliqué entre les deux plaques fait accélérer la particule selon une trajectoire rectiligne.

The accelerating field

field betweenelectrodes

zero fieldinside tube

negative electronaccelerated

+––

Principle of linear accelerator

Générateur de tension

+-

Le champ électrique

Ligne de champ électrique entre électrodes

Électron (négatif) accéléré

Principle of linear accelerator

The alternating p.d. switches back and forth so that the electrons are accelerated as they pass between successive electrodes

Switching p.d.s to keep accelerating electrons

at one instant alternating highfrequency p.d.

+

–

bunches of electrons betweenelectrodes are accelerated

a little later

a little later still

+

–

+ +– – –

bunches of electronsdrift through tube

bunches of electrons betweenelectrodes are further accelerated

+ +– – +

electrodes must be longer becauseelectrons are going faster

zero p.d.

–

+

+

–

À un instantPolarité négative

Groupe d’électrons entre deux électrodes est accéléré

Principle of linear accelerator

The alternating p.d. switches back and forth so that the electrons are accelerated as they pass between successive electrodes

Switching p.d.s to keep accelerating electrons

at one instant alternating highfrequency p.d.

+

–

bunches of electrons betweenelectrodes are accelerated

a little later

a little later still

+

–

+ +– – –

bunches of electronsdrift through tube

bunches of electrons betweenelectrodes are further accelerated

+ +– – +

electrodes must be longer becauseelectrons are going faster

zero p.d.

–

+

+

–

Un peu après

Zéro Groupe d’électrons dérivent dans le tube

Principle of linear accelerator

The alternating p.d. switches back and forth so that the electrons are accelerated as they pass between successive electrodes

Switching p.d.s to keep accelerating electrons

at one instant alternating highfrequency p.d.

+

–

bunches of electrons betweenelectrodes are accelerated

a little later

a little later still

+

–

+ +– – –

bunches of electronsdrift through tube

bunches of electrons betweenelectrodes are further accelerated

+ +– – +

electrodes must be longer becauseelectrons are going faster

zero p.d.

–

+

+

–

Encore un peu après

Polarité positive

Groupe d’électrons à nouveau accélérées

Électrodes plus longs, car électrons vont plus vite

1er terme de la loi de Lorentz

Hendrik Lorentz

(1853-1928)

13

Accélération circulaire: - La particule effectue une trajectoire courbe

Le champ magnétique crée par l’ aimant fait courber

la particule

2ème terme de la loi de Lorentz

Hendrik Lorentz

(1853-1928)

I

N

STrajectoire de la

particule

Particle accelerator. How it works

14

The Synchrotron accelerator

Le synchrotron – un accélérateur circulaire

AIMANT DE COURBURE

(DIPÔLES)

AIMANT FOCALISATEUR

(QUADRUPOLES)

CAVITÉ RADIOFRÉQUENCE

CIBLE

CHAMBRE À VIDE

Methods of Particle Physics

3) Identify created particles in Detector (search for new clues)

1) Concentrate energy on particles (accelerator)

2) Collide particles (recreate conditions after Big Bang)

http://pdg.web.cern.ch/pdg/particleadventure/

Today’s periodic system of the fundamental building blocks

The constituents of matter

The Atom’s Nucleus:Proton: 2/3 + 2/3 – 1/3Neutron: 2/3 – 1/3 – 1/3

We don't know everything!

Why three generations?

There are three "sets" of quark pairs and lepton pairs. Each "set" of these particles is called a generation, or family. Each set of quark and lepton charge types is called a generation of matter (charges +2/3, -1/3, 0, and -1 as you go down each generation). The generations are organized by increasing mass.

18

We don't know everything!

Supersymmetry?

Some physicists attempting to unify gravity with the other fundamental forces have come to a startling prediction: every fundamental matter particle should have a massive "shadow" force carrier particle, and every force carrier should have a massive "shadow" matter particle. This relationship between matter particles and force carriers is called supersymmetry. For example, for every type of quark there may be a type of particle called a "squark." No supersymmetric particle has yet been found, but experiments are underway at CERN and Fermilab to detect supersymmetric partner particles.

19

We don't know everything!

Higgs boson?

The LHC will help solving all these unsolved mysteries

The Standard Model cannot explain why a particle has a certain mass. For example, both the photon and the W particle are force carrier particles: why is the photon massless and the W particle massive? Physicists have theorized the existence of the so-called Higgs field, which in theory interacts with other particles to give them mass. The Higgs field requires a particle, the Higgs boson. The Higgs boson has not been observed, but physicists are looking for it with great enthusiasm.

Higgs signature at the LHC

We expect only 1 Higgs in 1,000,000,000,000 events

The two proton beams at the LHC will collide head-on 800 million times per second

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 S

I95

Moore’s law10K SI95 = 1200 cpu

LHC experimentsOther experiments

Evolution of CERN computing needsCPU capacity 1998-2010

The number of transistors per square inch on integrated circuits doubles every year and half

22

CERN, Internet and the WWW

The GRID: a possible solution to CERN computing needs

The LHC computing GRID is a project funded by the European Union. The objective is to build the next generation computing infrastructure providing intensive computation and analysis

24

Medical applications of particle physics

25

Summary

• CERN is the largest laboratory for particle physics research in the world

• It was founded 57 years ago and has built the most powerful particle accelerator in the world in 2008

• The particle physics studies the matter in its smallest dimension and deepens the human being’s understanding about the nature

• Research at CERN advances the development of technology, e.g. WWW was invented at CERN at the end of 1980’s

• Welcome to CERN, we wish you have a pleasant visit