Summary
The excitation of virtual Δ-isobar components in nuclei is discussed in a meson exchange model, including π and ρ exchange together with short-range correlations. We discuss the compatibility of predictions of this model with experimental information on isobar components from the (p,π −) reaction and the excitation of pionic, especially 1+, states. In view of the main obstacles for a direct evidence on virtual-isobar components, additional and more comprehensive experimental information and further theoretical progress is needed.
Riassunto
Si discute l’eccitazione delle componenti dell’isobaro Δ virtuali in un modello di scambio mesonico, includendo lo scambio di π e ρ insieme alle correlazioni a breve raggio. Si discute la compatibilità delle previsioni di questo modello con le informazioni sperimentali sulle componenti isobariche dalla reazione (p,π −) e l’eccitazione degli stati pionici, specialmente 1+. In vista degli ostacoli principali per una prova diretta dei componenti di isobari virtuali occorrono informazioni sperimentali piú ampie e ulteriori progressi teorici.
Резюме
Обсуждается возбуждение виртуальных Δ-изобарных компонент в ядрах в рамках модели с обменом мезонами, включая π и ρ обмен вместе с короткодействующими корреляциями. Мы обсуждаем совместимость предсказаний этой модели с экспериментальной информацией об изобарных компонентах из (p,π −) реакции и возбуждения пионных, особенно 1+, состояний. Для прямого подтверждения виртуальной изобарной примеси необходимы дополнительная и более всесторонняя экспериментальная информация и дальнейшие теоретические исследования.
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Dillig, M., Knüpfer, W. Virtual Δ-isobar admixture in nuclei. Nuov Cim A 76, 433–446 (1983). https://doi.org/10.1007/BF02833739
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DOI: https://doi.org/10.1007/BF02833739