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The invisible world The elementary particles

The invisible world The elementary particles. Study Nature’s phenomena… Look for the hidden laws behind these phenomena…. Experiment beyond our senses…. Scale factors.

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The invisible world The elementary particles

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  1. The invisible worldThe elementary particles

  2. Study Nature’s phenomena… Look for the hidden laws behind these phenomena…

  3. Experiment beyond our senses…

  4. Scale factors • Length (meters) 10-15 m = size of atom’s nucleus1 m = you4.10+16 m = distance that separate us from the star Alpha Centauri (4 light-years) • Time (seconds) 10-23 s = lifetime of particle Z01 s = you10+17 s = sun’s lifetime • Energies (Joules)10-19 J = energy of a photon emitted by a lamp 10-7 J = landing of a mosquito10+9 J = your meals during the day 10+16 J = atomic bomb of 1 Megaton 10+26 J = light energy from the sun…every second!

  5. Lets enter the invisible world 10 meters A rose tree

  6. Lets enter the invisible world 0.1 meter = 10 cm A fly on a rose tree leaf

  7. Lets enter the invisible world 10-3 meter = 1 mm The eye of a fly

  8. Detectors of the invisible The optical microscope Onions cells 10 micron

  9. Lets enter the invisible world 10-5 meter = 10 microns A hair on the eye of a fly

  10. Detectors of the invisible First electronic microscope : E. Ruska and M. Knoll , 1932 (Nobel prize 1986) The electronic microscope • = h / p l = longueur d’onde h = constante de Planck p = impulsion de la particule = mv Chloroplast within a plant cell Optical microscope Electronic microscope Light beam Electrons beam Optical lenses Electromagnetic lenses resolution 0.5 micrometer resolution 0.0002 micrometer 0.1 micron

  11. Lets enter the invisible world 10-7 meter = 0.1 micron The base of the hair and cells that make the eye of the fly

  12. A few examples of scalesThe small… You need the same number of cells to make a human being as stars to make a galaxy (100 billions)

  13. Lets enter the invisible world 10-8 meter ~ 100 Angströms A DNA strand within the nucleus of a cell

  14. Detectors of the invisible First scanning tunneling microscope: G. Binnig et H. Rohrer in 1981 (IBM, Zürich), Nobel prize 1986 Scanning tunneling microscope (STM) In 1990. the scanning tunneling microscope allowed researchers working at IBM to write the first letters in history written using nanotechnologies by placing 35 xenon atoms on a nickel surface. Voir aussi: http://www.cndp.fr/themadoc/micro3/rep_mcp.htm

  15. Lets enter the invisible world 10-10 meter = 1 Angström A carbon atom. It is one of the element that makes a molecule found in DNA Gold atoms deposited on a layer of carbon

  16. A few examples of scalesThe very small… You need as many atoms to make an orange as oranges to fill the Earth

  17. Lets enter the invisible world 10-14 meter = 10 fermis The nucleus of a carbon atom (drawing)

  18. A few examples of scalesThe very very small… You need as many atom’s nucleus to fill an atom as oranges to cover France entirely…15 times!

  19. Detectors of the invisible Experiment ALEPH, at CERN

  20. Lets enter the invisible world 10-15 meter = 1 fermi A proton in the nucleus (drawing) A proton contains 3 quarks

  21. Lets enter the invisible world

  22. At the end of the invisible world Nuclear physics and particle physics

  23. Elementary particles known in 2006

  24. Forces Strong interaction gluon quark quark 10-14 m

  25. Forces Electromagnetic interaction photon electron quark Billions of km

  26. Forces Weak interaction W+ neutrino quark 10-14 m n → p + e- + ne W+ W- Z0

  27. Unification of the interactions Unification of the 3 interactions: electromagnetic, weak and strong Weak interaction + electromagnetic interaction = electroweak interaction (1967-1973) Glashow, Salam, Weinberg Need Higgs 102 105 1010 1015 GeV 1 GeV = 1.6 1010 Joules

  28. Forces Gravitation interaction graviton electron quark Billions of km

  29. Lets summarize:Matter and forces… http://www.diffusion.ens.fr/vip/tableG00.html

  30. …and the anti-matter 1928 : P. Dirac predicts the existence of anti-matter Anti-electron trace in a C. Anderson bubble chamber 1932: C. Anderson discovers the anti-electron Collision between a electron and an anti-electron 1993: the LEP at CERN

  31. …anti-matter (2) C(A) C(B) CP(A) CP(B) A B Three fundamental transformations: P: parity inversion C: matter  anti-matter T: time reversal A B CPT(A) CPT(B) http://ppd.fnal.gov/experiments/e871/public/phys_slides.html

  32. …anti-matter (3) P Escher C CP

  33. …anti-matter (4) • Symmetry violated: P parity • Are there any other symmetries violated? Symmetry C matter ↔ anti-matter ? ≠ Left Right Left Left ? Right Right

  34. …anti-matter (5) Cosmic microwave background has been measured Today in our universe This ratio was though to be in the past • Diffuse cosmic background • First nucleosynthesis models • Number of stars At the beginning, for 1 billion anti-matter particles,there must have been 1 billion and 3 matter particles One condition:CP violation

  35. …anti-matter (6) The search for cosmic anti-matter To observe anti-matter in space, we « only » need sending a magnet Cosmic ray matter Anti-matter we can count cosmic rays and classify them by types The experiment AMS (Alpha Magnetic Spectrometer) was conceived to observe anti-matter in space

  36. …Anti-matter (7) A simple magnet is not enough, we also need a particle physics detector • AMS 02 • Space constraints • Mass < 7 t • 3 m x 3 m • Power consumption < 2 kW • Resistance : • Temperature -50° / +50° • Vacuum • Vibrations • ATLAS for the LHC • More than 7000 t • 44 m x 20 m • Power consumption > MW • Immobilised 100m under ground

  37. …anti-matter (8) Particle identification in AMS The detectors need to be very precise. We need to be able to reject: 1 proton in 104 positons 1 Helium in 103 positons 1 électron in 102 positons 1 proton in 106 photons

  38. Lets quickly go through history

  39. Experiments that changed everything E. Rutherford, H. Geiger et E. Marsdensent Helium particles (alpha particles) on gold leaf/sheet. … Surprise: the gold leaf/sheet looks like butter containing very small particles. Rutherford will interpret these as Gold atom’s nuclei

  40. ne 00ne W. Pauli suggests a new particle: the neutrino Experiments that changed everything The mystery of beta disintegration

  41. Experiments that changed everything 1 neutrino out 1020 interacts with the detector ! Reactor: 1020 neutrinos/sDetector at 12m3 neutrinos detected every hour water+cadmium The first neutrino detector. Built in 1956 by C. Cowan et F. Reines,near Savannah River’s nuclear reactor, USA

  42. Experiments that changed everything 1968 1974 1977 1983 1993 1995 SLAC: discovery of quarks Electrons-protons collisions SLAC and Brookhaven: discovery of quark « charme »electrons-positrons collisions Fermilab: discovery of quark « bottom »protons-protons collisions CERN: discovery of bosons W and Z protons-antiprotons collisions CERN: only three family of particles electrons-positrons collisions Fermilab: discovery of quark « top »proton-antiproton collisions

  43. Today’s experiments Giant detectors for tiny particles… SuperKamiokande track the sun’s neutrinos ALEPH detector studied high energy collisions

  44. The theory that changed everything…quantum mechanics Some of the players E. Fermidescribed weak interaction W. Paulipredicted the existence of the neutrino L. De Brogliepredicted wave-particle duality P. Diracpredicted the existence of anti-matter

  45. Quantum mechanicsa new way to see the invisible Particle and wave  wave function: y Ey = Hy Distribution of the probability of finding an electron in an atom Orbitale 2s Orbitale 2p Orbitale 3d z http://hypo.ge.ch/physic/simulations/orbitales/orbitales.html « Old » way to look at electrons in an atom

  46. The mystery of quantum mechanics Thomas Young’s experiment with photons

  47. The mystery of quantum mechanics Thomas Young’s experiment with electrons

  48. Small particles… awsome consequences Thermonuclear bomb

  49. Small particles… great consequences Proton therapy

  50. Seeking to understand what matter is made out of…Trying to see the invisible… …has led to a better understanding of the human body, our Sun inner workings, the development of new materials (semi-conductors) or new light sources (such as lasers)

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