Theory:
Interaction by particle exchange and QED Electron-positron annihilation
Elementary Particle Physics:
theory and experiments
Prof. dr hab. Elżbieta Richter-Wąs
Some slides taken from M. A. Thomson lectures at Cambridge University in 2011
Interaction by particle exchange and QED
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Recap
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Lecture 2
Skipped
In this Lecture will
Interaction by particel exchange
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Feynman diagrams
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Virtual particles
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Aside: V(r) from particle exchange
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Quantum Electrodynamics (QED)
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Virtuality in t-channel, not a charge!
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Feynman rules for QED
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Basic rules for QED
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Summary
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Electron-positron annihilation
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QED calculations
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Electron-positron annihilation
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Electron and muon currents
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Spin in e+e- annihilation
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The muon current
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Electron-positron annihilation cont.
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The electron current
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Matrix element calculation
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Differential cross-section
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Spin considerations (E>>m)
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Lorentz invariant form of ME
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Chirality
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Chirality
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Chirality in QED
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Allowed QED helicity combinations
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Summary
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