Summary
In this paper we discuss a method to calculate the axial nucleon form factorg A and the electromagnetic pion form factorF π from electroproduction data at threshold. The theoretical ingredients are gauge invariance, low-energy theorems and fixed-t dispersion relations. We also discuss the errors involved in the unavoidable approximations.
Riassunto
In questo articolo si discute un metodo per calcolare il fattore di forma assiale del nucleoneg A e il fattore di forma elettromagnetico del pioneF π da dati di elettroproduzione alla soglia. Gli strumenti teorici sono l’invarianza di gauge, i teoremi di bassa energia e le relazioni di dispersione at fissato. Si discutono anche gli errori derivanti dalle inevitabili approssimazioni.
Реэуме
В зтои работе мы обсуздаем метод вычисления аксиаляного нуклон-ного форм-фактораg A и злектромагнитного форм-фактора пионаF π иэ данных по злектророздениу на пороге. Теоретические ингредиенты представляут калибро-вочная инвариантностя, теоремы при ниэких знергиях и дисперсионные соотно-щения при фиксированномt. Мы такзе обсуздаем ощибки, фигурируушие в неиэ-безных приблизениях.
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Benfatto, G., Nicolò, F. & Rossi, G.C. Pion electroproduction at threshold. Nuov Cim A 14, 425–444 (1973). https://doi.org/10.1007/BF02756269
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DOI: https://doi.org/10.1007/BF02756269