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

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

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Il Nuovo Cimento A (1965-1970)

Summary

We found that the Regge-pole parameters obtained through a sum-rule integral over the low-energy πN data (phase shifts up toT π=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 (N α) trajectory exchange and no zero in the scattering amplitude associated with Δ exchange. The coupling of theN γ trajectory is weak throughout this region.

Riassunto

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 aT π=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 (N α) e nessuno zero nell'ampiezza d'urto associata allo scambio di Δ. In tutta questa regione l'accoppiamento della traiettoriaN γ è debole.

Резюме

Мы нашли, что параметры полюсов Редже, полученные с помощью интеграла правила сумм из πN данных при малых энергиях (сдвиги фаз вплоть доT π=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 (N α) траекторией, и отсутствие нуля в амплитуде рассеяния, связанной с Δ обменом. СвязьN γ траектории является слабой во всей этой области.

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Author notes

  1. C. B. Chiu

    Present address: High-Energy Theoretical Physics Group, CERN, Geneva

Authors and Affiliations

  1. Theoretical Group, Lawrence Radiation Laboratory, Berkeley, Cal

    C. B. Chiu

  2. Department of Physics, Temple University, Philadelphia, Pa

    M. DerSarkissian

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  1. C. B. Chiu
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  2. M. DerSarkissian
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Additional information

Part of this work was done under the auspices of the United States Atomic Energy Commission.

Traduzione a cura della Redazione.

Перевебено ребакцией.

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Chiu, C.B., DerSarkissian, M. Application of finite energy sum rules to πN scattering near the backward directionscattering near the backward direction. Nuovo Cimento A (1965-1970) 55, 396–411 (1968). https://doi.org/10.1007/BF02857562

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