Advertisement

Il Nuovo Cimento (1955-1965)

, Volume 38, Issue 3, pp 1385–1406 | Cite as

Two-particle and many-particle channels in high-energy collisions

  • A. Białas
  • L. Van Hove
Article

Summary

This paper continues previous investigations of high-energy collisions of hadrons in the asymptotic region of constant cross-sections. Two models proposed earlier, one in which inelastic collisions give rise to many particles with a minimum of correlation between them, the other in which they consist entirely of isobar excitation of one or both incident particles, are combined together and the resultant shadow scattering is compared with the experimental characteristics of elastic scattering. Excellent agreement is obtained if most of the inelastic collisions are of the uncorrelated many-particle type, only a small fraction of the inelastic cross-section corresponding to isobar excitation without further particle creation. The method used exploits unitarity of theS-matrix and crossing symmetry of the isobar excitation channels which are assumed to be dominated by 0=1 exchange. The isobar excitation channels are analysed in terms of a simpleK-matrix. The effect of the uncorrelated many-particle channels is described by means of an « overlap function » which determines the angular distribution of elastic scattering and isobar excitation. Its effect on the latter is found to be a simple generalization of the distorted wave Born approximation.

Riassunto

Si prosegue in questo articolo l’esatne delle collisioni di alta energia degli hadroni nella regione asintotica delle sezioni d’urto costanti. Si combinant) assieme due modelli proposti precedentemente, uno in oui le collisioni anelastiche danno origine a moite particelle con un minimo di correlazione fra loro, l’altro in cui esse consistono interamente di eccitazioni isobariche di una o di tutte e due le particelle incidenti, e si confronta 10 scattering ombra risultante con le caratteristiche sperimentali dello scattering elastico. Si ottiene un ottimo accordo se la maggior parte delle collisioni anelastiche sono del tipo a molte particelle non correlate, e solo una piccola percentuale della sezione d’urto anelastica corrisponde ad eccitazione isobarica senza ulteriore creazione di particelle. Il metodo usato sfrutta l’unitarietà della matrice S e la simmetria incrociata dei canali di eccitazione isobarica che si suppone siano dominati dallo scambio C=1. Si analizzano i canali di eccitazione isobarica in funzione di una matriceK semplice. Si descrive l’efietto dei canali a molte particelle non correlate per mezzo di una « funzione di sovrapposizione » che determina la distribuzione angolare dello scattering elastico e dell’eccitazione isobarica. Si trova che il suo effetto su quest’ultima è ana semplice generalizzazione dell’approssimazione di Born in onda distorta.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. (1).
    L. Van Hove:Rev. Mod. Phys.,36, 655 (1964).ADSCrossRefGoogle Scholar
  2. (2).
    A. Białas, Th. W. Ruijgrok andL. Van Hove:Nuovo Cimento,37, 608 (1965).CrossRefGoogle Scholar
  3. (3).
    W. N. Cottingham andR. F. Peierls:Phys. Rev.,137, B 147 (1965).MathSciNetADSCrossRefGoogle Scholar
  4. (4).
    O. Czyzewski, B. Escoubès, Y. Goldschmidt-Clermont, M. Guinea-Moorhsad, D. K. O. Morrison andS. de Unamuno-Escoubès:Phys. Lett.,15, 188 (1965).ADSCrossRefGoogle Scholar
  5. (6).
    M. Baker, andE. Blankenbecler:Phys. Rev.,128, 415 (1962).MathSciNetADSCrossRefGoogle Scholar
  6. (7).
    N. J. Sopkovich:Nuovo Cimento,26, 186 (1962).CrossRefGoogle Scholar
  7. (8).
    D. S. Chernavskii:Žurn. Ėksp. Teor. Fiz.,45, 1558 (1963); English translation:Sov. Phys. JETP,18, 1072 (1964).Google Scholar
  8. (9).
    A. Dar, M. Kuglbr, Y. Dothan andS. Nussinov:Phys. Rev. Lett.,12, 82 (1964).ADSCrossRefGoogle Scholar
  9. (10).
    A. Dak andW. Tobocman:Phys. B,ev. Lett.,12. 511 (1964).ADSCrossRefGoogle Scholar
  10. (12).
    L. Durand andY. T. Chiu:Phys. Rev. Lett.,12, 399 (1964); andSingle-particle exchange models for the reactions 7rp pp, -pp→-YY, np→pn, preprint (1964).ADSCrossRefGoogle Scholar
  11. (12).
    M. H. Boss andG. L. Shaw:Phys. Rev. Lett,12, 627 (1964).ADSCrossRefGoogle Scholar
  12. (13).
    K. Gottfried andJ. D. Jackson:Nuovo Cimento,34, 735 (1964).CrossRefGoogle Scholar
  13. (14).
    D. B. Lichtenberg andP. K. Williams:Multichannel approach to high-energy peripheral collisions, preprint (1964).Google Scholar
  14. (15).
    V. Barger:Nuovo Cimento,35, 700 (1965).CrossRefGoogle Scholar
  15. (16).
    R. C. Arnold:Phys. Rev.,136, B 1388 (1964).ADSCrossRefGoogle Scholar
  16. (17).
    R. Dietz andH. Pilkuhn:K-matrix model of peripheral interactions, CERN preprint (1964).Google Scholar
  17. (18).
    E. Omnès:Final-state interaction in the presence of absorption, UCRL preprint (1964).Google Scholar
  18. (19).
    E. J. Squires:Nuovo Cimento,34, 1328 (1964).MathSciNetCrossRefMATHGoogle Scholar

Copyright information

© Società Italiana di Fisica 1965

Authors and Affiliations

  • A. Białas
    • 1
  • L. Van Hove
    • 1
  1. 1.CERNGeneva

Personalised recommendations