Further remarks on ππ scattering dispersion relations
نویسندگان
چکیده
The naive use of higher order perturbation theory leads the left–hand cut integrals in ππ dispersion relations [1, 2] divergent. This problem is discussed and solved. Also we point out that the Adler zero condition imposes three constraints on the dispersion relations. The σ pole position is determined using the improved method, Mσ = 483 ± 13MeV,Γσ = 705 ± 50MeV. The scattering length parameter is found to be in excellent agreement with the experimental result. PACS numbers: 11.55.Bq, 14.40.Cs, 12.39.Fe
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تاریخ انتشار 2008