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Exploring High Energy Photon Collisions at LHC Physics Workshop

This workshop delves into the physics of ultra-peripheral nuclear collisions, focusing on particle production from electromagnetic fields, lepton-pair production, impact parameter dependence, and perturbative approaches. Key topics include collision parameters, relativistic colliders, heavy ion collisions, and quantum electrodynamics at high fields. Notable areas of study are direct and exchange diagrams, total cross section analysis, and the scalar part of electromagnetic fields. Experimental results from CERN's Super Proton Synchrotron and RHIC are examined, with discussions on electron-positron pair production, Coulomb corrections, and nuclear dissociation effects. The workshop aims to shed light on QED tests, photonuclear excitation, and kinematic restrictions for a better understanding of high-energy photon interactions.

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Exploring High Energy Photon Collisions at LHC Physics Workshop

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  1. Physics of Ultra-Peripheral Nuclear Collisions Cem Güçlü İstanbul Technical University Physics Department Workshop on “High energy photon collisions at the LHC

  2. Particle production from EMFields * Lepton-pair production * Beam Lifetime (electron capture) * Detector background * Non-perturbative and perturbative approach * Impact parameter dependence * Multi-pairproduction * Test of QED at high fields Workshop on “High energy photon collisions at the LHC

  3. Collision Parameters : Workshop on “High energy photon collisions at the LHC

  4. SPS 10 100 120 12 1.6 RHIC 100 10000 12000 1200 160 Relativistic Colliders Workshop on “High energy photon collisions at the LHC

  5. Collisions of Heavy Ions Workshop on “High energy photon collisions at the LHC

  6. Dirac wave-function of electrons/positrons Electromagnetic vector potential Electromagnetic field tensor Workshop on “High energy photon collisions at the LHC

  7. Lepton-Pair Production Semi Clasical Action : Free Lagrangian : Interaction Lagrangian : Workshop on “High energy photon collisions at the LHC

  8. Four Vector Potentials of the Colliding Ions : Workshop on “High energy photon collisions at the LHC

  9. Ion 1 Ion 2 time Pair Production Emits photon Emits photon Workshop on “High energy photon collisions at the LHC

  10. Direct and exchange diagrams : Workshop on “High energy photon collisions at the LHC

  11. Total Cross Section Workshop on “High energy photon collisions at the LHC

  12. Scalar part of EM Fields in momentum space of moving heavy ions Workshop on “High energy photon collisions at the LHC

  13. Free electron-positron pair production SPS , γ=10, Au + Au , σ=140 barn RHIC, γ=100, Au + Au , σ=36 kbarn LHC, γ=3400, Au + Au , σ=227 kbarn Bound- free electron-positron pair production RHIC, γ=100, Au + Au , σ=83 barn LHC, γ=3400, Au + Au , σ=161 barn Pb + Pb, σ=206 barn Workshop on “High energy photon collisions at the LHC

  14. Impact Parameter Dependence Cross Sections : Workshop on “High energy photon collisions at the LHC

  15. Workshop on “High energy photon collisions at the LHC

  16. Workshop on “High energy photon collisions at the LHC

  17. Workshop on “High energy photon collisions at the LHC

  18. Two Photon Method : Equivalent Photon Method: M. C. Güçlü, Nucl. Phys. A, Vol. 668, 207-217 (2000) Workshop on “High energy photon collisions at the LHC

  19. Workshop on “High energy photon collisions at the LHC

  20. Workshop on “High energy photon collisions at the LHC

  21. Born Approximation with Coulomb Corrections R.N.Lee at al, Phys. Rev. A 64, 032106 (2001) Workshop on “High energy photon collisions at the LHC

  22. Workshop on “High energy photon collisions at the LHC

  23. Workshop on “High energy photon collisions at the LHC

  24. Workshop on “High energy photon collisions at the LHC

  25. Small momentum approximation M.C. Güçlü at al. Phys. Rev. A 72 022724 (2005). Workshop on “High energy photon collisions at the LHC

  26. Experiments at CERN Super Proton Synchroton SPS Workshop on “High energy photon collisions at the LHC

  27. Energy = 200 A GeV at fixed target frame Measured Cross Section for 1-17 MeV /c positron yield with 25% error for 1-17 MeV /c positron For all positron momenta Vane CR at al. Phys. Rev. A 50:2313 (1994). Workshop on “High energy photon collisions at the LHC

  28. Workshop on “High energy photon collisions at the LHC

  29. Workshop on “High energy photon collisions at the LHC

  30. Workshop on “High energy photon collisions at the LHC

  31. What about experiments at SOLENOIDAL TRACKER ( STAR ) ? RHIC: Relativistic Heavy Ion Collider Energy =100 GeV/nucleon Au + Au collisions Circumference = 2.4 miles Workshop on “High energy photon collisions at the LHC

  32. Cross Section of electron-positron pairs accompanied by nuclear dissociation Giant Dipole Resonance Workshop on “High energy photon collisions at the LHC

  33. Why do we study the reaction ? • The test of QED at high fields – are there indications that • at the available energies more than two photons are • involved in an electron-positron pair creation? • 2. Is pair production is independent of photonuclear excitation? Workshop on “High energy photon collisions at the LHC

  34. No hadronic probability, computed with Woods-Saxon nuclear form factor Workshop on “High energy photon collisions at the LHC

  35. Probability of mutual Coulomb nuclear excitation with breakup as a function of impact parameter G. Baur at al. Nuclear Physics A 729 (2003) 787-808 Workshop on “High energy photon collisions at the LHC

  36. Kinematic restrictions at STAR experiment Rapidity: Invariant mass: Transverse momentum : Adams J. At al. Phys. Rev. A 63:031902 (2004) Workshop on “High energy photon collisions at the LHC

  37. Results: Baur at al. : σ = 1.9 mb Workshop on “High energy photon collisions at the LHC

  38. Adams J. At al. Phys. Rev. A 63:031902 (2004) Workshop on “High energy photon collisions at the LHC

  39. Adams J. At al. Phys. Rev. A 63:031902 (2004) Workshop on “High energy photon collisions at the LHC

  40. FAIR - Facility for Antiproton and Ion Research Completed in 2015 Cost : 1.2 billion Euro QED Strong Fields Ion -Matter Interactions Workshop on “High energy photon collisions at the LHC

  41. CONCLUSIONS: 1. We have obtained impact parameter dependence of lepton-pair production probability by using the semi-classical two photon method. 2. At SPS and RHIC energies, Monte Carlo QED calculations agree well with the experimantal results. 3. Can we use this method to calculate the production of other particles such as mesons, heavy leptons, may be Higgs particles ? 4. Can RHIC be used to test QED? 5. Cross section for bound-free pair production is very large and this will limit the maximum Pb-Pb luminosity at the LHC. Therefore we should understand these QED effects to a high degree of accuracy. Workshop on “High energy photon collisions at the LHC

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