PHYS3321 Nuclear and Particle Physics

1. PHYS3321 Nuclear and Particle Physics

2. Course coordinator Prof. Zhang Fu-Chun • Head & Chair Professor • Department of Physics • fuchun@hku.hk • Room 517 A, Chong Yuet Ming Building Tutor • Mr. HUO Jia-wei • Address: Room 418, Chong Yuet Ming Building (Physics department) • Email: jiaweihuo@gmail.com • Phone: 95106582

3. PHYS3321 Textbook

4. To the late Prof. C.D. Beling This lecture notes are based on the course materials by the late Prof. C.D. Beling, who taught this course over the past a few years in the physics department of HKU.

5. Four Assignments + mid-term test: 30%Examination (3 hours): 70% SCHEDULE Tuesdays 9:30 – 11:25 MW322 Thursdays 10:30 – 11:25 MW702 PHYS3321 Course Assessment

6. Continuous Assessment • Four Assignments + 1 mid-term test + attendance • 30% of overall weighting Mid–term test: Mar. 1st 10:30-11:25 AM

7. Course requirements • Four Assignments + 1 mid-term test + attendance • 30% of overall weighting • End of Semester Exam • 70% of overall weighting • Prerequisite: • Pass in PHYS2321(Introductory electromagnetism) and PHYS2322(Statistical mechanics and thermodynamics) and PHYS2323(Introduction to Quantum Mechanics)

8. PHYS3321 course schedule

9. PHYS3321 course schedule

10. PHYS3321 course schedule (detailed)

11. PHYS3321 course schedule (detailed)

12. Where to get the course materials http://www.physics.hku.hk/~phys3321/ This course website will update every week You must check this website to download • lecture notes • Assignment questions • Assignment answers • Other information…

13. This course Nuclear physics + Particle physics

14. What will this course cover Nuclear physics • Rutherford Scattering • Electron scattering • Nuclear binding energy • Liquid drop model • Nuclear shell model • Alpha decay • Beta decay • Fission Schematic diagram of Rutherford Scattering http://en.wikipedia.org

15. What will this course cover Nuclear physics • Rutherford Scattering • Electron scattering • Nuclear binding energy • Liquid drop model • Nuclear shell model • Alpha decay • Beta decay • Fission

16. What will this course cover Nuclear physics • Rutherford Scattering • Electron scattering • Nuclear binding energy • Liquid drop model • Nuclear shell model • Alpha decay • Beta decay • Fission http://library.thinkquest.org/

17. What will this course cover Nuclear physics • Rutherford Scattering • Electron scattering • Nuclear binding energy • Liquid drop model • Nuclear shell model • Alpha decay • Beta decay • Fission http://library.thinkquest.org/

18. What will this course cover Nuclear physics • Rutherford Scattering • Electron scattering • Nuclear binding energy • Liquid drop model • Nuclear shell model • Alpha decay • Beta decay • Fission

19. What will this course cover Particle physics (see the next a few slides) • Particle Classification • Quark Composition of Hadrons • Conservation Laws • Particle Reactions and Decays • The standard model • Grand Unified Theory

21. Fundamental building block of baryons and mesons

22. The six quarks

23. Large Hadron Collider Experiment http://www.hep.phys.soton.ac.uk/~belyaev/teaching/phys3002/notes.html

24. Particle physics:The standard model

25. The standard model The Standard Model of elementary particles, with the gauge bosons in the rightmost column From: http://en.wikipedia.org

26. The standard model Summary of interactions between particles described by the Standard Model. From: http://en.wikipedia.org

27. The Four Fundamental Forces

28. Practical Applications • Nuclear fission for energy generation. • No greenhouse gases • Safety and storage of radioactive material. • Nuclear fusion • No safety issue (not a bomb) • Less radioactive material but still some. • Nuclear transmutation of radioactive waste with neutrons. • Turn long lived isotopes  stable or short lived. • Every physicist should have an informed opinion on these important issues! *Slide by Tony Weidberg

29. Medical Applications • Radiotherapy for cancer • Kill cancer cells. • Used for 100 years but can be improved by better delivery and dosimetery • Heavy ion beams can give more localised energy deposition. • Medical Imaging • MRI (Nuclear magnetic resonance) • X-rays (better detectors  lower doses) • Positron emission tomography (PET) • Many others…see Medical & Environmental short option. *Slide by Tony Weidberg

30. Medical Applications 3He magnetic resonance imaging of the lung Non-smoker Light smoker Mainz University and University hospital Mainz, 1999

31. Other Applications • Radioactive Dating • C14/C12 gives ages for dead plants/animals/people. • Rb/Sr gives age of earth as 4.5 Gigayear (1 Gigayear= 1×109 years). • Element analysis • Forenesic (eg date As in hair). • Biology (eg elements in blood cells) • Archaeology (eg provenance via isotope ratios). *Slide by Tony Weidberg

32. Nuclear physics history

33. History facts • Bequerel • Discovers natural radioactivity in Uranium salts. Conclusions – the Uranium atom is unstable • J. J. Thompson • Discovers the electron in “cathode rays” and measures e/me

34. 1898 Wein - Discovers the proton in the “Canal rays” of H2 discharge. A positive particle ~2000 times mass of electron. 1898 Mdm and Pierre Currie find new naturally occuring radioactive atoms – Polonium and Radium.

35. 1899 – 1903 Discovery of the α, β and γ components of nuclear radiation 1900 – 1910 Thomson model of the atom prevailed Proton charge evenly distributed over size of 1Å. Electrons imbedded and oscillatory.

36. 1911 The Nuclear Hypothesis. Rutherford postulated that the positive charge of the atom lay in a “nucleus”. The electrons circulated around the nucleus to form the atom. Moreover Rutherford and his coworkers tested this model experimentally by scattering alpha particles from the nucleus. The data confirmed the nuclear model and not the Thompson model. Nuclear radius less than =1fm= 1 Fermi Charge on nucleus = atomic number =Z

37. 1913 Bohr publishes the first quantum theory of the H-atom based on the nuclear model 1911 – 1932 Electron + Protons model of nucleus • During the 1920s this model came under criticism from many physicists. • How could the electrons be confined • How could the spins of nuclei be accounted for? Rutherford suggested that there must be another particle called the Neutron inside the nucleus Spin

38. 1932 Neutron discovered by Chadwick 1932 Heisenberg - formalizes neutron + proton model of nucleus

39. Discovery of Nuclear Fission – Hahn, Meitner and Strassman • 1939 Liquid Drop Model completed • 1942 First Controlled Fission • 1945 First Fission Bomb • Pi meson discovered by Powel • 1949 Shell Model of Nuclear Structure completed • (Mayer, Jensen, Haxel, Suess)

40. Particle physics history

41. Matter equates with Energy E=mc2 Energy Mass

42. Cockroft and Walton http://homepage.eircom.net/~louiseboylan/Pages/Cockroft_walton.htm • 1931, First artificial splitting of nucleus • Also the first transmutation using artificially accelerated particles • And the first experimental verification of E = mc2 John Cockcroft Ernest Walton Nobel Prize 1951

43. Cockroft and Walton http://homepage.eircom.net/~louiseboylan/Pages/Cockroft_walton.htm • 1931, First artificial splitting of nucleus • Also the first transmutation using artificially accelerated particles • And the first experimental verification of E = mc2 1 MeV 17.3 MeV Proton + Lithium Two alpha particles + Energy

44. History of Particle Physics 1935 Hideki Yukawa published his theory of mesons, which explained the interaction between protons and neutrons, and was a major influence on research into elementary particles. Yukawa’s theory predicted that there was a particle – the Pion – that mediated the strong nuclear force that bound neutrons and protons together in the nucleus Hideki Yukawa (1907 – 1981)

45. History of Particle Physics 1932 Carl Anderson working with high altitude cloud chamber discovers the positron (The anti-particle of the electron) as predicted by Dirac’s theory 1936 Anderson also discovers the Muon – (then known as the Mu-Meson) The Muon was originally thought to be the Yukawa particle (Pion) because it had a mass in the right range ~ 200 me. However the Muon did not interact with neutrons or protons. We now know the Pion is the parent of the Muon. Carl Anderson (1905 – 1991) Pions decay into two particles, a muon and a muon neutrino or antineutrino

46. History of Particle Physics 1947 Cecil Powell and collaborators at Bristol University UK finally discovered the Pion in short tracks in nuclear emulsions. Cecil Powell (1903 – 1969)

47. History of Particle Physics • First Proton Synchrotron 2.3GeV (Brookhaven) • 1953 First production of Strange particles • 1955 Anti-proton produced • 1956 Parity violation discovered (C.S. Wu) • 1964 Quark model proposed (Gell-Mann, Zweig) • 1967 Electroweak model proposed (Weinberg, Salam) • 1974 Charm quark discovered (Richter, Ting) • 1977 Bottom quark discovered (Lederman) • 1983 W and Z particles discovered (CERN) • 1996 Top quark discovered (Fermi Lab)

48. Today’s Particle physics

49. Particle Physics: searching for Higgs Boson 2011 First hard evidence of God particle (Higgs boson) was found by CERN researchers --- yet to be confirmed in 2012 A typical 'candidate event' for the Higgs boson, including two high-energy photons whose energy (depicted by red towers) is measured by CMS. The yellow lines are the measured tracks of other particles produced in the collision

50. Particle Physics: searching for Higgs Boson The CMS detector weighs a staggering 13,000 tons. CMS is a particle detector that is designed to see a wide range of particles and phenomena produced in high-energy collisions in the Large Hadron Collider (LHC) . Like a cylindrical onion, different layers of detectors measure the different particles, and use this key data to build up a picture of events at the heart of the collision