Il Nuovo Cimento A (1971-1996)

, Volume 55, Issue 3, pp 396–411 | Cite as

Application of finite energy sum rules to πN scattering near the backward directionscattering near the backward direction

  • C. B. Chiu
  • M. DerSarkissian


We found that the Regge-pole parameters obtained through a sum-rule integral over the low-energy πN data (phase shifts up toTπ=1.3 GeV) and over the σ-pole contribution in thet-channel, nearu=0, are compatible with the available Regge parameters obtained at high energy. In particular in the interval fromu=0.1 to −0.35 (GeV)2 we predict a zero in the scattering amplitude associated with the nucleon (Nα) trajectory exchange and no zero in the scattering amplitude associated with Δ exchange. The coupling of theNγ trajectory is weak throughout this region.

Применение правил сумм при конечний энергии к πN рассеянию вблизи направления назадрассеянию вблизи направления назад


Мы нашли, что параметры полюсов Редже, полученные с помощью интеграла правила сумм из πN данных при малых энергиях (сдвиги фаз вплоть доTπ=1.3 (ГэВ)) и из вклада σ-полюса вt-канале, вблизиu=0, является совместимым с имеющимися параметрами Редже, полученными при высоких энергиях. В частности, в интервале отu=0.1 до −0.35 (ГэВ)2 мы предсказываем нуль в амплитуде рассеяния, связанной с обменом нуклонной (Nα) траекторией, и отсутствие нуля в амплитуде рассеяния, связанной с Δ обменом. СвязьNγ траектории является слабой во всей этой области.


Si trova che i parametri dei poli di Regge ottenuti integrando la regola di somma rispetto ai dati di πN di bassa energia (spostamenti di fase fino aTπ=1.3 GeV) e al contributo del polo σ nel canalet, vicino au=0, sono compatibili con i parametri di Regge disponibili ottenuti ad alta energia. In particolare, nell'intervallo dau=0.1 a −0.35 (GeV)2 si predice uno zero nell'ampiezza di scattering associata allo scambio di traiettoria del nucleone (Nα) e nessuno zero nell'ampiezza d'urto associata allo scambio di Δ. In tutta questa regione l'accoppiamento della traiettoriaNγ è debole.


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Copyright information

© Società Italiana di Fisica 1968

Authors and Affiliations

  • C. B. Chiu
    • 1
  • M. DerSarkissian
    • 2
  1. 1.Theoretical GroupLawrence Radiation LaboratoryBerkeley
  2. 2.Department of PhysicsTemple UniversityPhiladelphia

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