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Il Nuovo Cimento A (1965-1970)

, Volume 20, Issue 1, pp 35–48 | Cite as

Kn→Ση near threshold

  • R. Y. L. Chu
  • J. Bartley
  • R. Dowd
  • J. Schneps
  • J. Tompkins
  • G. Wolsky
  • L. Kirsch
  • P. Schmidt
Article

Summary

The reaction Kn→Ση has been studied near threshold. The production angular distribution and the cross-section as a function of energy were measured. The combined angular distributions of this experiment and two previous ones suggest that aJ=1/2 amplitude dominates in Ση production. Our cross-section can be fitted with a Σ−1η resonance of mass 1785±12 and width 89±33, or it can be fitted in a zero-effective-range scattering approximation with a scattering length of (0.92±0.12)±i(0.04±0.28) fm.

Реакция Kn→Ση вблиэи порога

Реэюме

Исследуется реакция Kn→Ση вблиэи порога. Иэмеряются угловое распределение рождения и поперечное сечение, как функция знергии. Общединенные угловые распределения зтого зксперимента и двух предыдуших укаэывают, что амплитудаJ=1/2 доминирует в Ση рождении. Полученное поперечное сечение может быть согласовано с Ση реэонансом с массой 1785±12 и щириной 89±33, или может быть согласовано в приближении нулевой зффективной области рассеяния с длиной рассеяния, равной (0.92±0.12)±i(0.04±0.28)fm.

Riassunto

Si è studiata la reazione Kn → Ση nei pressi della soglia. Si sono misurate la distribuzione angolare della produzione e la sezione d’urto in funzione dell’energia. Le distribuzioni angolari combinate di questo esperimento e di due precedenti suggeriscono che un’ampiezzaJ=1/2 domina nella produzione Ση. Si può approssimare la nostra sezione d’urto con una risonanza Ση di massa 1785±12 e ampiezza 89±33 o, in una approssimazione di scattering di rango effettivo zero, con una lunghezza di scattering di (0.92±0.12)±i(0.04±0.28) fm.

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Copyright information

© Società Italiana di Fisica 1974

Authors and Affiliations

  • R. Y. L. Chu
    • 1
  • J. Bartley
    • 2
  • R. Dowd
    • 2
  • J. Schneps
    • 2
  • J. Tompkins
    • 2
  • G. Wolsky
    • 2
  • L. Kirsch
    • 3
  • P. Schmidt
    • 3
  1. 1.Department of Physics, State University of New YorkCollege of Arts and SciencePlattsburgh
  2. 2.Department of PhysicsTufts UniversityMedford
  3. 3.Department of PhysicsBrandeis UniversityWaltham

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