QED processes in two photon reactions

Conference paper
Part of the Lecture Notes in Physics book series (LNP, volume 191)


I review experimental results on the reactions e+e → e+ee+e and e+e → e+e μ+μ from PETRA and PEP. Recent high statistics measurements are compared to QED predictions in the form of diagrammatic leading order (α4) calculations and to the equivalent photon approximation. The leading order calculation describes the data well over the full kinematic range covered by experiments (0.1 ≲ Q2 ≲ 100 GeV2/c2).The “two photon interaction”graph is found to saturate the observed cross section. Only for small masses of the produced leptonic system, first indications of a bremsstrahlung type background are observed at the percent level. The leptonic structure function F2γ(x, Q2) is measured and also agrees with the behavior expected from QED. photon approximation. Under most conditions, the “two-photon interaction” graph alone adequately accounts for the data. Only at x = 1, a “bremsstrahlung” background at the percent level is observed. The structure function approach gives an appropriate description of the data on eγ → eμμ. The measured “muonic” structure function <F 2 γ (x, Q2)> agrees with the behavior expected from QED.


Structure Function Pair Production Lepton Pair Photon Interaction Muon Pair 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. (1).
    J. Builey et al., Nucl. Phys. B150, 1 (1979).Google Scholar
  2. (1a).
    R.S. Van Dyck, P.B. Schwingberg and H.G. Dehmelt, Phys. Rev. Lett. 38, 310 (1979).Google Scholar
  3. (1b).
    K. von Klitzing, G. Dorda and M. Pepper, Phys. Rev. Lett. 45, 494 (1980).Google Scholar
  4. (2).
    J. Behrend et al., Z. Phys. C16, 301 (1983).Google Scholar
  5. (2a).
    W. Bartel et al., Phys. Lett. 108B, 160 (1982) and DESY 83-035.Google Scholar
  6. (2b).
    B. Adeva et al., Phys. Rev. Lett. 48, 1701 (1982).Google Scholar
  7. (2c).
    Ch. Berger et al., Phys. Lett. 99B, 292 (1981).Google Scholar
  8. (2d).
    R. Brandelik et al., Phys. Lett. 117B, 365 (1982).Google Scholar
  9. (2e).
    E. Fernandez et al., Phys. Rev. Lett. 50, 1238 (1983).Google Scholar
  10. (3).
    R. Bhattacharya, J. Smith and G. Grammer, Phys.Rev. D15, 3267 (1977).Google Scholar
  11. (3a).
    J.A.M. Vermaseren, Proc. of the Int. Workshop on γγ Collisions, Amiens 1980, G. Cochard and P. Kessler Edts, Lecture Notes in Physics 134, 35 (1980).Google Scholar
  12. (3b).
    S. Kawabata, see J. Field, Proc.of the 4th Int.Workshop on Photon-Photon Interactions, G.W. London Edt., Paris 1981, p. 447.Google Scholar
  13. (4).
    J.A.M. Vermaseren, Contribution to this conference.Google Scholar
  14. (4a).
    Ph. Daverveldt, Contribution to this conference.Google Scholar
  15. (5).
    see V.M. Buchner, T.F. Ginzburg, G.V. Meledin and V.G. Serbo, Phys. Rep. 15, 181 (1975).Google Scholar
  16. (6).
    J.H. Field, Nucl. Phys. B168, 477 (1980); B176, 345 (1980).Google Scholar
  17. (6a).
    Ch. Berger and J.H. Field, Nucl. Phys. B187, 585 (1981).Google Scholar
  18. (7).
    A. Coureau, CAL 82/19 (1982).Google Scholar
  19. (8).
    CELLO Collaboration, H.J. Behrend et al., DESY 83/017 (1983).Google Scholar

Copyright information

© Springer Verlag 1983

Authors and Affiliations

  • M. Pohl
    • 1
  1. 1.III. Phys. Inst. A R W T H AachenGermany

Personalised recommendations