Il Nuovo Cimento A (1965-1970)

, Volume 49, Issue 4, pp 555–576 | Cite as

A study of the quark rearrangement model of nucleo-antinucleon annihilation

  • J. Harte
  • R. H. Socolow
  • J. Vandermeulen
Article

Summary

A model of proton-antiproton annihilation via quark rearrangement suggested by Rubinstein and Stern is examined in detail. This model predicts that all final states are three-meson states, made from the set π, η, X, ρ, ω, and allows a computation of their relative rates. Its predictions are compared with experimental data at rest and at several energies in flight. The model is found not to be able to account for more than 25% of the annihilations at rest, event when maximum freedom is given to certain extra parameters. The model underestimates the importance of high-multiplicity states in annihilations, in flight and also fails to predict the more detailed features of these data. A number of interesting aspects of the data are uncovered and possible directions along which the model might be modified are suggested.

Keywords

Vector Meson Annihilation Rate Spin Wave Function Strange Meson Charged Meson 
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.

Изучение усоверщенствованной модели кварков для аннигиляции нуклона и антинуклона

Рзеюме

Подробно исследуется модель аннигиляции протона и антипротона через усовершенствованную модель кварков, предложенную Рубинштейном и Штерном. Эта модель предсказывает, что все конечные состояния являются трехмезонными состояниями, образованными из системы π, ν, X, ρ, ω, и делает возможным вычисление их относительных скоростей. Предсказания этой модели сравниваются с экспериментальными данными для аннитиляции в покое и для некоторых энергий на лету. Обнаружено, что эта модель не может объяснитя более чем 25% аннигиляций в покое, даже когда имеет максимум свободы для некоторых дополнителяных параметров. Эта модель недооценивает важности высокой множественности состояний при аннигиляции на лету и также не предсказывает более подробных особенностей экспериментальных данных. Обнаруживается ряд интересных особенностей для этих данных, и предлагаются возможые направления, где эта модель может быть видоизменена.

Riassunto

Si esamina in dettaglio un modello di annichilazione protone-antiprotone tramite il riordinamento di quark suggerito da Rubinstein e Stern. Questo modello predice che tutti gli stati finali sono stati di tre mesoni, composti dal gruppo π, ν, X, ρ, ω e permette il computo dei loro rapporti relativi. Se ne confrontano le predizioni con i dati sperimentali in quiete ed a parecchie energie in volo. Si trova che il modello non è in grado di render conto di più del 25% delle annichilazioni in quiete, anche quando si lascia la massima libertà ad alcuni parametri addizionali. Il modello sottovaluta l'importanza degli stati di elevata molteplicità nelle annichilazioni in volo e anche manca di predire le più dettagliate caratteristiche di questi dati. Si svela una quantità di aspetti interesanti dei dati e si suggeriscono le possibili direzioni in cui il modello potrebbe essere modificato.

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References

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Copyright information

© Società Italiana di Fisica 1967

Authors and Affiliations

  • J. Harte
    • 1
  • R. H. Socolow
    • 1
  • J. Vandermeulen
    • 1
  1. 1.CERNGeneva

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