1 / 42

La classificazione delle particelle elementari

La classificazione delle particelle elementari. The zoo of the elementary particles. Spezia Stefano Catania 21 Agosto 2013. Elementary particles. Matter. Force Carriers. Quarks. Leptons. Gravitons. ?. W & Z Bosons. Photons. Gluons. Quark-Lepton complementarity. Hadrons. Strong.

tyrone
Télécharger la présentation

La classificazione delle particelle elementari

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. La classificazione delle particelleelementari The zoo of the elementary particles Spezia Stefano Catania 21 Agosto 2013

  2. Elementary particles Matter Force Carriers Quarks Leptons Gravitons ? W & Z Bosons Photons Gluons Quark-Lepton complementarity Hadrons Strong Gravity Weak Electromagnetism Baryons Quantum Gravity Quantum Chromodynamics Quantum Electrodynamics Mesons Nuclei Electroweak Theory Atoms Grand Unified Theory Molecules Theory of everything

  3. Raccomandazione (2006/962/CE) Tra le 8 competenze chiave per l’apprendimento permanente: • Comunicazione nelle lingue straniere • Competenza matematica e competenze di base in scienza e tecnologia • Competenza digitale

  4. … con il CLIL? • Titolo del modulo: The zoo of the elementary particles • Classe:V LiceoScientifico • Raccordiinterdisciplinari:Chimica, Inglese • Competenzelinguistiche:Inglese • Risorse e strumenti:LavagnaInterattivaMultimediale (LIM) • Periodoscolastico: 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)

  5. Obiettivi: 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.

  6. LESSON PLAN: Lesson 1 • Introduction to … (tempo 10 minuti): Main question? • ‪Attivita’ di brainstorming (tempo 20 minuti): La classe viene sollecitata a riflettere sul alcune domande fondamentali; ogni alunno dà il suo contributo alla discussione • Lezione interattiva con stimolo di interventi alla LIM da parte degli studenti, per proporre le proprie risposte alle questioni scientifiche presentate.

  7. The world around us • What is the world made of? • What are the building blocks that could not be further divided? • 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

  8. What is the world made of? • In the ancient time: 4 elements • 17-19th century – molecules and atoms • 20th century – electrons, protons and neutrons • Today – quarks and leptons The atom in the 20th century... • Atoms reacts through chemical reactions • More than 100 atoms known (H, He, Fe …) • The internal structure is not well known

  9. The modern atom Atomic Model • A cloud of electrons moving constantly around the nucleus • Protons and neutrons moving in the nucleus • Quarks moving in protons and neutrons

  10. Sub-atomic dimensions Nucleus • 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!

  11. Sub-atomic dimensions Nucleus are made of neutrons and protons! Neutrons andprotons are made of quarks! Quarks andelectrons are elementary particles!

  12. Particle physics …small, smaller…extremely small!… > 30 soccer fields Point-like Point like < 1 hair A small stone

  13. New 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.

  14. How can we observe these particles? 1897 - Joseph John Thomson discovers a particle, later calledElectron

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

  16. Cosa possiamo osservare con essa?

  17. Cosa possiamo osservare con essa?

  18. Teoria Lezionefrontale (2.5 ore)

  19. Standard model A 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.

  20. 2/3 -1/3 0 -1 Example of the standard model Proton: u + u + d quark Neutron: u + d + d quark Carbon: 18 u, 18 d, 6 e- Quarks Leptons

  21. Pauli principle 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. Fermions Leptons and quarks Baryons Bosons Force carrier particles Mesons Spin = 1/2 Spin = 1 Spin = 1/2, 3/2, 5/2 … Spin = 0, 1, 2 …. Hadrons

  22. 2nd generation 3rd generation 2/3 2/3 -1/3 -1/3 0 0 -1 -1 Fermions: the fundamental components 1st generation Massa (MeV) Charge (e) Quarks Leptons

  23. Matter 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.

  24. Forces in Nature There are 4 fundamental interactions! The force carrier is the photon (γ) -massless and move at the speed of light Gravity is very weak and is important at macroscopic distances The interactions are also responsible of the nucleus decays. 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

  25. Forces in Nature Interactions happen by exchange of one or more particles (carriers or bosons)

  26. Forces and distances R > 106 m (gravitational) R ~ 10-11 - 10-10 m (electroweak) R ~ 10-15 m (strong nuclear)

  27. The gluon A heavy nucleus contains many protons, all with positive charges. These protons repulse each others. Why the nucleus does not explode? The strong force keeps the quark together, to form the hadrons. The force carriers are the gluons: there are 8 different gluons.

  28. Coloured quarks and gluons There are 3 colour charges and 3 anti-colour charges 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

  29. Baryons and Mesons as coloured 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.

  30. 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.

  31. Fase applicativa (1,5 ore): Utilizzo di Flash 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). • Gruppiomogeneidialunni; • Gruppieterogeneidialunni.

  32. Tra gli esercizi per casa… Applicazioni per dispositivi Android (giochi, simulatori, wallpaper, strumenti di misura virtuali, calcolatori, tascabili (pockets),…) Physics: The Standard Model

  33. Verifica sommativa e valutazione • La verifica è fornita in inglese e propone quattro tipologie di esercizi: • VERO O FALSO? • Risposta singola • Risposta multipla • Frasidacompletare • Gli esercizi possono essere risolti, senza che sia richiesto agli studenti la totale padronanza nella composizione in lingua inglese. Hanno invece sicuramente bisogno della comprensione durante la lettura per capire la consegna.

  34. 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! Single answer • What is the charge of an UP quark (in unit of the elementary charge e)? • -1; • -1/3; • 2/3; • +1. • What is the charge of a DOWN quark? • -1; • -1/3; • 2/3; • +1.

  35. Esempio di prova di verifica Single answer • What is the quark composition of a proton? • ddd; • ddu; • duu; • uuu. • What is the quark composition of a neutron? • ddd; • ddu; • duu; • uuu.

  36. Esempio di prova di verifica Single answer • Which of the four fundamental forces is not included in the Standard Model? • Electromagnetic; • Gravitational; • Strong Nuclear; • Weak Nuclear. • Which of the fundamental forces has a range of only a few angstroms (0.1 nm)? • Electromagnetic; • Gravitational; • Strong Nuclear; • Weak Nuclear.

  37. Esempio di prova di verifica True or False • Single quarks have been observed experimentally; • 3rd generation quarks (TOP and BOTTOM) are constituents of everyday matter; • The W-, W+, and Z0 bosons are carriers for the weak nuclear force which is responsible for radioactive decay; • MeV/c2 and GeV/c2 are units which are dimensionally equivalent to grams according to Einstein's equation, E = mc2. False False True False

  38. Esempio di prova di verifica Multiple answer • Which of the fundamental force(s) have an infinite range? • Electromagnetic; • Gravitational; • Strong Nuclear; • Weak Nuclear.

  39. Esempio di prova di verifica Complete the phrases 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; Higgs Electrons strong

  40. Esempio di prova di verifica Open questions What is the difference between hadrons and leptons? What is the difference between fermions and bosons? What is the difference between baryons and mesons?

  41. 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..

  42. Bibliografia • 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

More Related