Summary
Superconvergent sum rules are derived for πN *→πN *, two of which agree withU 6,6 when saturated byN andN poles in the equal-mass limit. Saturation for physical masses givesГ N *=84 MeV. It is pointed out that those sum rules which agree withU 6,6 for πN→πN * and πN *→πN * do so also for all analogous strange-particle reactions. The special status of these sum rules is discussed.
Riassunto
Si derivano regole di somma superconvergenti per πN *→πN *; due di esse risultano in accordo col gruppoU 6,6 quando siano saturate da poliN eN al limite di masse uguali. La saturazione per masse fisiche dàГ N *=84 MeV. Si fa vedere che quelle regole di somma che sono in accordo col gruppoU 6,6 per reazioni πN→πN * e πN *→πN *, lo sono anche per tutte le reazioni analoghe di particelle strane. Si discute lo stato speciale di queste regole di somma.
Резюме
Выводятся сверхсходящиеся правила сумм для πN *→πN *, два из которых согласуются сU 6,6, при насыщении полюсамиN иN в пределе равных масс. Насыщение для физических масс даётГ N *=84 МэВ. Отмечается, что эти правила сумм, которые согасуются сU 6,6, для πN→πN * и πN *→πN *, также согласуются для всех аналогичных реакций странных частиц. Обсуждается особое положение этих правил сумм.
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References
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The research reported in this document has been sponsored in part by the Air Force Office of Scientific Research OAR through the European Office Aerospace Research, United States Air Force.
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Jones, H.F., Scadron, M.D. U 6,6 and superconvergent sum rules for meson-baryon scattering. Nuovo Cimento A (1965-1970) 52, 62–72 (1967). https://doi.org/10.1007/BF02739273
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DOI: https://doi.org/10.1007/BF02739273