La classificazione delle particelle elementari Spezia Stefano Catania 21 Agosto 2013 The zoo of the elementary particles

La classificazione delle particelleelementari

Spezia Stefano

Catania 21 Agosto 2013

The zoo of the elementary particles

Elementary particles Elementary particles

MesonsBaryons

Nuclei

Atoms

Molecules

Quark-Leptoncomplementarity

Matter

Quarks Leptons

Hadrons

?

Theory of everything

Force Carriers

Gluons

W & Z Bosons GravitonsPhotons

Strong

QuantumChromodynamics

Gravity

QuantumGravity

WeakElectromagnetism

QuantumElectrodynamics

Electroweak Theory

Grand Unified Theory

Raccomandazione (2006/962/CE)Raccomandazione (2006/962/CE)

Tra le 8 competenze chiave per l’apprendimento le 8 competenze chiave per l’apprendimento permanente:permanente:

Comunicazione nelle lingue straniere

Competenza matematica e competenze di base in scienza e tecnologia

Competenza digitale

… … con il CLIL?con il CLIL? Titolo del modulo: The zoo of the elementary particles Classe: V Liceo Scientifico Raccordi interdisciplinari: Chimica, Inglese Competenze linguistiche: Inglese Risorse e strumenti: Lavagna Interattiva Multimediale

(LIM) Periodo scolastico: ultime 3 settimane di Maggio Prerequisiti: Meccanica (Forze ed interazioni, Teoremi

di conservazione); Meccanica relativistica (Equivalenza massa-energia, dilatazione del tempo); Elementi di Quanti, Materia e Radiazione.

Numero di ore: 8,5 Compresenza: Insegnante di Inglese (3,5 ore)

Obiettivi: Competenze per i giovaniObiettivi: Competenze per i giovani

Conoscenze Saper descrivere le principali famiglie di particelle

elementari; Saper descrivere le principali interazioni e le loro

fondamentali proprietà;

Abilità ed Attitudini essenziali (connessioni con la realtà) Essere in grado di leggere e capire un articolo

divulgativo su particelle elementari e le loro interazioni.

LESSON PLAN: Lesson 1LESSON PLAN: Lesson 1

The world around usThe world around us

1. What is the world made of?

2. What are the building blocks that could not be further divided?

3. What is the smallest particle you know?

Look at the following links and find information about the building blocks of our world:

http://www.infn.it/multimedia/particle/paitaliano/summary_sm.html

http://www.infn.it/multimedia/particle/paitaliano/exp_start.html

http://www.infn.it/multimedia/particle/paitaliano/beyond_start.html

What is the world made of?What is the world made of? In the ancient time: 4 elements4 elements 17-19th century – moleculesmolecules and atomsatoms 20th century – electrons, protons electrons, protons and neutrons neutrons Today – quarks and leptonsquarks and leptons

The atom in the 20The atom in the 20thth century... century... Atoms reacts through chemical reactions More than 100 atoms known (H, He, Fe …) The internal structure is not well known

Atomic ModelAtomic ModelThe modern atomThe modern atom

A cloud of electrons moving constantly around the nucleus

Protons and neutrons moving in the nucleus

Quarks moving in protons and neutrons

Sub-atomic dimensionsSub-atomic dimensions

NucleusNucleus The nucleus is small and

dense. For a while it was thought to be point-like.

However, there were so many different nuclei as many atoms

Simplification: all nuclei are made of neutrons and protons!

Sub-atomic dimensionsSub-atomic dimensions

Nucleus Nucleus are made of neutrons and protons!

Neutrons Neutrons and protons protons are made of quarks!

Quarks Quarks and electrons electrons are elementary particles!

Particle physicsParticle physics

Point like

Point-like

……small, smaller…extremely small!small, smaller…extremely small!…

A small stone< 1 hair

> 30 soccer fields

New particlesNew particles Collisions of electrons and nuclei in the cosmic rays

and in the particle accelerators brought to the discovery of many other particles.

At the beginning it was thought that all these particles were fundamentals.

How can we observe these particles?How can we observe these particles?

1897 - Joseph John Thomson discovers a particle, later called Electron

Laboratorio con materiale povero: Laboratorio con materiale povero: camera a nebbia FAI DA TE (2 ore)camera a nebbia FAI DA TE (2 ore)

Cosa possiamo osservare con essa?Cosa possiamo osservare con essa?

Cosa possiamo osservare con essa?Cosa possiamo osservare con essa?

TeoriaTeoria

Lezione frontaleLezione frontale (2.5 ore) (2.5 ore)

Standard modelStandard modelA theory has been developed that seems to explain quite well what we do observe in nature. This model includes 6 quarks, 6 leptons and 13 particles which carry the force in between quarks and leptons.

Example of the standard modelExample of the standard model

Quarks

Leptons

2/3

-1/3

0

-1

Proton: u + u + d quarkNeutron: u + d + d quark

Carbon: 18 u, 18 d, 6 eCarbon: 18 u, 18 d, 6 e--

Pauli principlePauli principle

FermionsFermions

Leptons and quarks

Baryons

BosonsBosons

Force carrier particles

Mesons

Spin = 1/2 Spin = 1

Spin = 1/2, 3/2, 5/2 … Spin = 0, 1, 2 ….

Bosons all fall into the lowest energy state, forming a Bose Einstein condensate.

Fermions, must obey the Pauli exclusion principle, which prohibits two identical particles

from occupying the same state.

Hadrons

Fermions: the fundamental Fermions: the fundamental componentscomponents

Quarks

Leptons

2/3

-1/3

0

-1

1st generation 2nd generation 3rd generation

2/3

-1/3

0

-1

Massa (MeV) Charge (e)

Matter and Anti-matterMatter and Anti-matter

For every particles there is a corresponding particle of anti-matter, or anti-particle

These particles appear to be as their sisters of matter, but with opposite charge

Particles are created or destroyed with their antiparticles.

The interactions are also responsible of the nucleus decays.

Forces in NatureForces in NatureThere are 4 fundamental interactions!

Gravity is very weak and is important at

macroscopic distances

The force carrier is the photon (γ) -

massless and move at the speed of light

In adding to the electrical charge,

Quarks have another kind of

charge called “color charge”

Weak interactions are responsible for

the decays of heavy quarks and

leptons

Forces in NatureForces in Nature

ForceForce IntensityIntensity CarriersCarriers Happens inHappens in

Strong Nuclear ~ 1Gluons

(massless)Atomic nuclea

Elettromagnetic ~ 10-3Photons

(massless)Atomic levels

Weak Nuclear ~10-5W+,W-,Z0

(heavy)Beta radioactive

decay

Gravitation ~10-38

Gravitons

(not observed)

Heavy bodies

Interactions happen by exchange of one or more particles (carriers or bosons)

Forces and distances

R ~ 10-15 m (strong nuclear)

R ~ 10-11 - 10-10 m (electroweak)

R > 106 m (gravitational)

A heavy nucleus contains many protons, all with positive charges. These protons repulse each others. Why the nucleus does not explode?

The gluonThe gluon

The strong force keeps the quark together, to form the hadrons. The force carriers are the gluons: there are 8 different gluons.

There are 3 colour charges and 3 anti-colour charges

Coloured quarks and gluonsColoured quarks and gluons

Every quark has one of the three colour charges and every anti-quark has one of the three anti-colour charges

Baryons R + G + B = white

Mesons color + anti-color = white

Baryons and Mesons as Baryons and Mesons as coloured quarkscoloured quarks

All baryons, such as the proton and neutron shown here, are composed of three quarks. All mesons, such as the pions shown here, are composed of a quark-antiquark pair.

What can we say about mass?What can we say about mass? The SM cannot explain

why a given particle is characterized by its mass.

Physicists “invented” a new particle, called Higgs boson, which interacts with all the other particles to give their masses.

Its discover has been announced on 4 July 2012 and confirmed in March 2013.

Fase applicativa (1,5 ore): Fase applicativa (1,5 ore): Utilizzo di Utilizzo di Flash Learning ObjectsFlash Learning Objects

THE FIREWORKS OF THE ELEMENTARY PARTICLE PHYSICS

By

Elena Symeonidou

Applicazione guidata e controllata, con esercizi interattivi da parte degli studenti e supervisione costante dell'insegnante (approccio collaborativo).

Gruppi omogenei di alunni;

Gruppi eterogenei di alunni.

Tra gli esercizi per casa…Tra gli esercizi per casa…Applicazioni per dispositivi Android (giochi, simulatori, wallpaper, strumenti di misura virtuali, calcolatori, tascabili (pockets),…)

Physics: Physics: The Standard ModelThe Standard Model

Verifica sommativa e valutazioneVerifica sommativa e valutazione

Esempio di prova di verifica (1.5 ore)Esempio di prova di verifica (1.5 ore)Try to make each initial answer correct. Don't just guess - research and

show me that you have learned the correct answers. Be careful!

1. What is the charge of an UP quark (in unit of the elementary charge e)?

a. -1;b. -1/3;c. 2/3;d. +1.

2. What is the charge of a DOWN quark?a. -1;b. -1/3;c. 2/3;d. +1.

Single answerSingle answer

Esempio di prova di verificaEsempio di prova di verifica

3. What is the quark composition of a proton?

3. ddd;

4. ddu;

5. duu;

6. uuu.

4. What is the quark composition of a neutron?

a. ddd;

b. ddu;

c. duu;

d. uuu.



5. Which of the four fundamental forces is not included in the Standard Model?

a. Electromagnetic;

b. Gravitational;

c. Strong Nuclear;

d. Weak Nuclear.

6. Which of the fundamental forces has a range of only a few angstroms (0.1 nm)?

a. Electromagnetic;

b. Gravitational;

c. Strong Nuclear;

d. Weak Nuclear.


1.Single quarks have been observed experimentally;

2.3rd generation quarks (TOP and BOTTOM) are constituents of everyday matter;

3.The W-, W+, and Z0 bosons are carriers for the weak nuclear force which is responsible for radioactive decay;

4.MeV/c2 and GeV/c2 are units which are dimensionally equivalent to grams according to Einstein's equation, E = mc2.

True or FalseTrue or False


False

True

False

False

1. Which of the fundamental force(s) have an infinite range?

a. Electromagnetic;

b. Gravitational;

c. Strong Nuclear;

d. Weak Nuclear.


Multiple answerMultiple answer

Interactions with the ______ boson gives particles their unique masses;

______ and neutrinos are classified as leptons;

Gluons are the bosons, or force carriers, for the _____ force which holds nuclear particles and the nucleus together;


Complete the phrasesComplete the phrases

Higgs

Electrons

strong

What is the difference between hadrons and leptons?

What is the difference between fermions and bosons?

What is the difference between baryons and mesons?


Open questionsOpen questions

The Particle Physicist’s Bible: Particle Data Bookhttps://pdg.lbl.gov

"Young man, if I could remember

the names of these particles,

I would have been a botanist!“

E. Fermi to his student

L. Lederman (both Nobel laureates)

Most particles are not stable and can decay to lighter particles..

BibliografiaBibliografia

Paul Davies, Superforza, Arnoldo Mondadori Editore S. p. A. 1986

Ugo Amaldi, La fisica di Amaldi, Zanichelli editore, 2007

George Gamow, The Great Physicists from Galileo to Einstein, Dover publications 1986

Jonathan Allday, Quarks, Leptons and The Big Bang, IOP Publishing 2002

M. G. Veltman, Martinus Veltman, Facts and Mysteries in Elementary Particle Physics, World Scientific Publishing- Singapore, Ed. 2003

Documents

La classificazione delle particelle elementari Spezia Stefano Catania 21 Agosto 2013 The zoo of the elementary particles