Summary
A dual relativistic quark model is constructed for ππ and πN scattering amplitudes. The model has satisfactory high-energy behaviour and mass spectrum, no parity doubling on leading trajectories, and at a pole the leading-trajectory contribution factorizes into a product of collinearU 6 ⊗O 2 covariant vertices. The model is found to give satisfactory predictions fors-wave scattering lengths. It is also compared with the current algebra and partially conserved axial vector current predictions and is found to be compatible with them. The implications of the model for understanding the latter are also discussed.
Riassunto
Si costruisce un modello duale relativistico a quark per ampiezze di diffusione ππ e πN. Il modello ha spettro di masse e comportamento ad alte energie soddisfacenti, nessuno sdoppiamento dovuto a parità sulle traiettorie principali ed a un polo il contributo della traiettoria principale è fattorizzabile in un prodotto di vertici covarianti per la simmetriaU 6 ⊗O 2 collineare. Il modello dà predizioni soddisfacenti per le lunghezze di diffusione di ondas. Inoltre lo si confronta con le predizioni dell’algebra delle correnti e della conservazione parziale della corrente assiale e si trova che esso è compatibile con queste predizioni. Si discutono inoltre implicazioni del modello per capire queste ultime.
Реэюме
Для амплитуд ππ и πN рассеяния конструируется дуальная релятивистская модель кварков. Эта модель имеет удовлетворительное поведение при высоких знергиях и массовый спектр. В модели отсутствует удвоение четности на главных траекториях, и в полюсе вклад главных траекторий факториэуется в проиэведение коллинеарныхU 6 ⊗O 2 ковариантных верщин. Получается, что зта модель дает удовлетворительные предскаэания для длинsволнового рассеяния. Полученные предскаэания сравниваются с предскаэаниями алгебры токов и частично сохраняюшегося аксиального векторного тока. Обнаружено раэумное согласие между зтими предскаэаниями. Также обсуждаются следствия зтой модели для интерпретации частично сохраняюшегося аксиального векторного тока.
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Work supported in part by the Istituto Nazionale di Fisica Nucleare.
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Venturi, G. Low-energy aspects of a dual relativistic quark model. Nuov Cim A 6, 499–515 (1971). https://doi.org/10.1007/BF02723382
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DOI: https://doi.org/10.1007/BF02723382