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Hadron physics at ISR energies

  • M. Jacob
Colliding Beam Physics
Part of the Lecture Notes in Physics book series (LNP, volume 37)

Keywords

Transverse Momentum Wide Angle Inclusive Distribution Streamer Chamber Cluster Picture 
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References and footnotes

  1. 1.
    Proc. 1973 Lovain Summer Institute in Theoretical Physics (Plenum Press, New York, 1974). The abbreviations used throughout are: ISR (Intersecting Storage Rings, CERN); NAL (National Accelerator Laboratory, Batavia, Illinois, now FermiLab); SPS (Super Proton Synchrotron, CERN, presently being constructed).Google Scholar
  2. 2.
    Studies for antiproton storage give a luminosity of the order of 1025, which is very low for experimentation.Google Scholar
  3. 3.
    A guided tour around the ISR, with 6 intersections used for physics now includes the following set-ups: I1 Saclay double-arm spectrometer used in coincidence with the CERN-Columbia-Rockefeller lead-glass detector. I2 British barrel detector used in coincidence with the CERN-Holland-Lancaster-Manchester small-angle spectrometer and the former British-Scandinavian wide-angle spectrometer. 14 Extensive research programme with the split field magnet detector (four different experiments with machine time so far). I6 Analysis of several particles at the same time through a wide acceptance magnet (Aachen-CERN-UCLA) and then more precise measurements of da/dt. I7 Aachen-CERN-Heidelberg-Munich streamer chamber used in coincidence with a wide-angle lead-glass detector. I8 Pisa-Stony Brook 4π detector used in coincidence with a lead-glass detector, the CERN-Rome forward spectrometer, the Scandinavian-MIT wide angle spectrometer, etc.Google Scholar
  4. 4.
    See also J.D. Jackson, in Proc. Scottish Universities Summer School (1973).Google Scholar
  5. 5.
    For a discussion of phenomenological duality see K. Igi, Phenomenological duality, to be published in Phys. Reports; M. Jacob, Regge models and duality, in Proc. Brandeis University Summer School (1970).Google Scholar
  6. 6.
    A. Melissinos, Invited paper, APS Chicago meeting (1974).Google Scholar
  7. 7.
    A. Melissinos, to be published in Phys. Reports.Google Scholar
  8. 8.
    The ISR results are reviewed by U. Amaldi, Rapporteur's talk, Aix-en-Provence Conference, 1973.Google Scholar
  9. 7.
    H. Miettinen, Rencontre de Moriond, CERN preprint (1974).Google Scholar
  10. 8.
    L. Foà, Rapporteur's talk, Aix-en-Provence Conference, 1973.Google Scholar
  11. 9.
    For a review, see S. Fubini, Multiperipheral Dynamics, Scottish Universities Sommer School (1963).Google Scholar
  12. 10.
    The definition of cluster properties from correlations in the central region is discussed in Ref. 1. For a detailed review of clustering effects and their observation through statistical analysis see R. Slansky, to be published in Phys. Reports 11 C.Google Scholar
  13. 11.
    Saclay-CERN-Columbia-Rockefeller Collaboration, Contribution to 17th Int. Conf. on High-Energy Physics, London, 1974.Google Scholar
  14. 12.
    Pisa-Stony Brook Collaboration, Contribution to the 17th Int. Conf. on High-Energy Physics, London 1974. For a detailed discussion see ISR summary 9, CERN internal report (1974). Similar results have since been obtained by the Aachen-CERN-Heidelberg-Munich streamer chamber experiment.Google Scholar
  15. 13.
    One may generalize this procedure and try to isolate a term independent of n (varying ΔY) and ΔY (varying n) in C3 (n) (ΔY/n) or R3 (n)(n/ΔY) and identify it with \(\frac{{\left\langle {K\left( {K - 1} \right)\left( {K - 2} \right)} \right\rangle n}}{{\left\langle K \right\rangle _n }}D^{\left( {^3 } \right)} \left( {v_1^2 ,v_2^2 ,v_3^2 } \right)\) with \(v_i = Y - y_i and Y\frac{1}{3} = \left( {y_1 + y_2 + y_3 } \right)\) This is very interesting in view of the value tentatively attributed to 〈K〉. This, however, requires very large statistics. The procedure is to isolate the short-range correlation term and identify it with what is expected from particles produced from the same cluster.Google Scholar
  16. 14.
    Scandinavian Collaboration, K. Hansen, private communication.Google Scholar
  17. 15.
    US-USSR Collaboration at NAL, Contribution to 17th Int. Conf. on High-Energy Physics, London, 1974.Google Scholar
  18. 16.
    M. Jacob and R. Stroynowski, The shape of the quasi-elastic peak, to be published in Nuclear Phys. Of particular interest is the presence of a structure at |t| ∼ 0.3 (GeV/c)2, which would be associated with an important peripheral no-helicity flip contribution. This could correspond to most of the non-resonant “background” when coherently produced.Google Scholar
  19. 17.
    The ISR can be considered as a “Pomeranchon accelerator” in the same energy range as SLAC is a “photon accelerator”.Google Scholar
  20. 18.
    J. Whitmore and T. Ferbel, private communications.Google Scholar
  21. 19.
    R.P. Feynman, Photon-hadron interactions, Benjamin Frontiers series (Benjamin, NY, 1971).Google Scholar
  22. 20.
    J. Kogut and L. Susskind, Physics Reports 8 C, 75 (1973)CrossRefGoogle Scholar
  23. 21.
    S.D. Ellis and M.B. Kisslinger, to be published in Phys. Rev.Google Scholar
  24. 20.
    S. Berman, J. Bjorken and J. Kogut, Phys. Rev. D4, 3388 (1971).Google Scholar
  25. 22.
    M. Jacob and S. Berman, Phys. Rev. Letters 25, 183 (1970).Google Scholar
  26. 23.
    R. Blankenbecler, S. Brodsky and F. Gunion, Rev. D6, 2652 (1972); D8, 287 (1973).Google Scholar
  27. 24.
    P. Landshoff and J. Polkinghorne, as reviewed by J. Polkinghorne, Aix-en-Provence Conference, 1973.Google Scholar
  28. 21.
    There is no theory for large p phenomena. There are many models which are not reviewed here. One should consult J. Bjorken, Rapporteur's talk, Aix-en-Provence Conference, 1973; P. Landshoff, Rapporteur's talk, 17th Int. Conf. on High-Energy Physics, London, 1974Google Scholar
  29. 22.
    S. Ellis and R. Thun, Rencontre de Moriond, 1974.Google Scholar
  30. 22.
    The theoretical aspect of large transverse momentum phenomena in the parton picture is described by J. Polkinghorne in his series of lectures (Bonn Institute).Google Scholar
  31. 23.
    Chicago-Princeton Collaboration, Contribution to 17th Int. Conf. on High-Energy Physics, London, 1974.Google Scholar
  32. 24.
    This was the situation at the time of the 1973 Aix-en-Provence Conference (results from the CCR Collaboration as discussed by J. Bjorken).Google Scholar
  33. 25.
    The inclusive distribution is then written as dδ/dpT2 = (l/s2) G(xT), since s is the only quantity with a dimension. This can of course be rewritten as dσ/dpT2 = (l/pT 4) F(xT). A different function F should appear for different production angles. Since all available data are at 90° this is often omitted.Google Scholar
  34. 26.
    This was emphasized by P. Darriulat in his invited paper at the Trieste Topical Conference on Intersecting Storage Rings Physics, 1974.Google Scholar
  35. 27.
    Confusion between ν and π) (γ-rays are detected) with different bias in the two experiments may explain, at least partly, the actual discrepancy. To the extent that there is an important K/π ratio at large pT (0.3 say), one may expect also a sizeable ν/π ratio.Google Scholar
  36. 28.
    What is meant by “no” is that in most cases, all the secondaries seen on the same side are soft (pT ∼ 0.4 GeV/c). This does not exclude low probability configurations with two (several) large pT particles. They, however, do not contribute much to the inclusive yield (Fig. 15).Google Scholar
  37. 29.
    British-Scandinavian Collaboration, Contribution to the 17th Int. Conf. on High-Energy Physics, London, 1974.Google Scholar
  38. 30.
    The p/π+ is found to decrease with the atomic number. Chicago-Princeton Collaboration, Contribution to the 17th Int. Conf. on High-Energy Physics, London, 1974.Google Scholar
  39. 31.
    Another possible picture is that of a heavy central fireball with approximate isotropic decay. It would trap the two positive charges and give accordingly a positive excess. One would not expect charged yields at large p to factorize in opposite directions as one would expect in the parton picture.Google Scholar
  40. 32.
    Results reported at the London Conference indicate a large increase of the number of soft secondaries with increasing PT, while the probability of finding harder ones increases strongly. This occurs on both sides. Most of the associated secondaries are soft.Google Scholar
  41. 33.
    Aachen-CERN-Heidelberg-Munich Collaboration, ISR summary 10, CERN internal report (1974). I am indebted to P. Darriulat for many discussions about this experiment.Google Scholar
  42. 34.
    Two topics, large transverse momentum phenomena and diffractive excitation are covered in more detail in M. Jacob, Erice Lecture Notes (1974). The discussion on particle correlation given here follows what was presented at the Trieste Topical Conference on Intersecting Storage Rings Physics, unpublished, 1974.Google Scholar

Copyright information

© Springer-Verlag 1975

Authors and Affiliations

  • M. Jacob
    • 1
  1. 1.CERNGenevaSwitzerland

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