Advertisement

Jet Phenomena

  • Maurice Jacob
Part of the NATO Advanced Study Institutes Series book series (NSSB, volume 66)

Abstract

While quarks do not appear as such, they may leave a clear kinematical signature. Spectacular trails of π mesons, such as those shown in Fig. l.a, have now become almost commonplace. An electron-positron annihilation here results in a two-jet pattern. Jets of π mesons appear instead of the quark-antiquark final state system, in terms of which many features of the reaction can be interpreted. The appearance of such jets is usually described in terms of the two-time scale, familiar to the parton model1. A primeval process occurs on a very short time scale. It is described in terms of hadron constituents (partons) and results in a final set of partons moving away in a particular configuration. Partons then eventually turn into actual hadrons through a process which occurs on a longer time scale. This process is known to be “soft”. It involves only limited transverse momentum with respect to the parton direction (with an exponentially damped distribution associated with hadronic size). As a result, the final (π meson) pattern retains many kinematical features of the primeval parton one, provided that particle momenta are large enough, or that the reaction energy is sufficiently high, in practice of the order of 10 GeV or more at the parton level2.

Keywords

Transverse Momentum Transverse Momentum Distribution Thrust Distribution Trigger Particle TASSO Collaboration 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References and Footnotes

  1. 1.
    R.P. Feynman, “Photon-Hadron Interactions”, Benjamin, Reading, MASS. (1972).Google Scholar
  2. 5.
    M. Jacob, Rapporteur talk EPS Conference, Geneva (1979) p. 473. A very detailed review of jet properties is to be found in W. Hofmann, “Jets of Hadrons”, Habilitationsschrift, University of Dortmund (1980).Google Scholar
  3. 6.
    These general properties of hadronic processes are described in several review articles. See for instance: L. Van Hove, Phys. Rep. 1, 347 (1971)CrossRefGoogle Scholar
  4. 6a.
    D. Horn, Phys. Rep. 4, 1 (1972)CrossRefGoogle Scholar
  5. 6b.
    W. Frazer et al., Rev. Mod. Phys. 44, 284 (1972)CrossRefGoogle Scholar
  6. 6c.
    G. Giacomelli and M. Jacob, Phys. Rep. 55, 1 (1979).CrossRefGoogle Scholar
  7. 7.
    R. Feynman and R. Field, Nucl. Phys. B, 136, 1 (1978).CrossRefGoogle Scholar
  8. 9.
    M. Gell-Mann, Acta Physica Austriaca Suppl. 9, 733 (1972). Quantum Chromodynamies, Proc. the La Jolla 1978 Institute, W. Frazer, F. Henyey edGoogle Scholar
  9. 9a.
    H.D. Politzer, Phys. Rep. 14, 129 (1974)CrossRefGoogle Scholar
  10. 9b.
    W. Marciano and H. Pagels, Phys. Rep. 36, 139 (1978)CrossRefGoogle Scholar
  11. 9c.
    Yu. L. Dokshitzer, D.I. Dyakonov and S.I. Troyan, Phys. Rep. 58, 269 (1980).CrossRefGoogle Scholar
  12. 10.
    S. Ellis, Proc. Boulder Summer School, 1979Google Scholar
  13. 11.
    P. Hoyer, Proc. Sakopane Summer School, 1979Google Scholar
  14. 12.
    D. Sivers, R. Blankenbecler and S. Brodsky, Phys. Rep. 23, 1 (1976)CrossRefGoogle Scholar
  15. 12a.
    S. Ellis and R. Stroynowski, Rev. Mod. Phys. 49, 753 (1977)CrossRefGoogle Scholar
  16. 12c.
    P. Darriulat, Ann. Rev. Mod. Sc. to be published (1980).Google Scholar
  17. 13.
    G. Hanson et al., Phys. Rev. Lett. 35, 196 (1975)CrossRefGoogle Scholar
  18. 13a.
    G. Feldman and M. Perl, Phys. Rep. 33, 285 (1977)CrossRefGoogle Scholar
  19. 13b.
    H. Meyer, Proc. CERN-DESY School, Malente (1980).Google Scholar
  20. 14.
    J. Ellis and Ch. Sachrajda, Proc. Cargèse Summer School (1979)Google Scholar
  21. 14a.
    J.D. Björken, Proc. SLAC Summer School (1979)Google Scholar
  22. 14b.
    E. Reya, Phys. Rep., to be published (1980).Google Scholar
  23. 17.
    For detailed reviews of features and concepts in particle production one should consult E. Feinberg, Phys. Rep. 5, 237 (1972)CrossRefGoogle Scholar
  24. 17a.
    I.M. Dremin and A.M. Dunaerskii, Phys. Rep. 18, 159 (1975)CrossRefGoogle Scholar
  25. 17b.
    R. Slansky, Phys. Rep. 11, 99 (1974)CrossRefGoogle Scholar
  26. 17c.
    L. Foa, Phys. Rep. 22, 1 (1975)CrossRefGoogle Scholar
  27. 17d.
    J. Whitmore, Phys. Rep. 10, 273 (1974), 27, 187 (1976).CrossRefGoogle Scholar
  28. 18.
    S. Fubini, Scottish Universities Summer School (1963).Google Scholar
  29. 21a.
    Nucl. Phys. B 134, 189 (1978)CrossRefGoogle Scholar
  30. 21b.
    Phys. Rev. Lett. 42, 1202 (1979)CrossRefGoogle Scholar
  31. 21c.
    J. Rohlf, Caltech Thesis (1980).Google Scholar
  32. 23.
    R. Horgan and M. Jacob, CERN TH 2824 (1980) and Proc. CERN-DESY School, Malente (1980).Google Scholar
  33. 33.
    G. Sterman and S. Weinberg, Phys. Rev. Lett. 39, 1436 (1977).CrossRefGoogle Scholar
  34. 35.
    Ch. Llewellyn-Smith, Proc. Schladming Winter School (1978)Google Scholar
  35. 37.
    Our discussion follows Dokshitzer et al. Ref. 9, which should be consulted for a more detailed analysis. See also G. Veneziano, Proc. Johns Hopkins Florence Meeting, G. Domokos ed., (1979) and J. Kogut and L. Susskind, Phys. Rev. D9, 697 (1974).Google Scholar
  36. 38.
    K. Konishi, A. Ukawa and G. Veneziano, Phys. Lett. 78 B, 243 (1978)Google Scholar
  37. 38a.
    A. Krischner, Phy. Lett. 84 B, 266 (1979).CrossRefGoogle Scholar
  38. 39.
    G. Altarelli and G. Parisi, Nucl. Phys. B 126, 298 (1977).CrossRefGoogle Scholar
  39. 41.
    D. Amati and G. Veneziano, Phys. Lett. 83 B, 87 (1979).Google Scholar
  40. 45.
    J. Ellis, M.K. Gaillard and G.C. Ross, Nucl. Phys. B 111, 253 (1976)CrossRefGoogle Scholar
  41. 45a.
    B 130, 516 (1976)Google Scholar
  42. 45b.
    A. de Rujula et al., Nucl. Phys. B 238, 387 (1978).CrossRefGoogle Scholar
  43. 48.
    J.D. Björken, Phys. Rev. D 17, 171 (1978).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1981

Authors and Affiliations

  • Maurice Jacob
    • 1
  1. 1.CERNGenevaSwitzerland

Personalised recommendations