Comments on the σ and κ

  title={Comments on the $\sigma$ and $\kappa$},
  author={David V. Bugg},
  • D. Bugg
  • Published 16 October 2003
  • Physics
The determination of σ and κ poles is discussed. Elastic scattering and production processes may be fitted simultaneously by including the Adler zero into the Breit‐Wigner width Γ(s). Data on ππ → ππ and Ke4 decays give a σ pole at (525 ± 40) − i(247 ± 25) MeV. A combined analysis with production data gives a better determination: (542 ± 25) − i(249 ± 25) MeV. The Fourier transform of the matrix element for σ → ππ reveals a compact interaction region with RMS radius ∼ 0.4 fm. The analysis of… 

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