M. C. Menchaca Maciel

arXiv2010

Sigma meson resonance and its coupling constant

We study two coupling constants reported as predictions of the sigma model. We obtain an spectral distribution, in terms of the σmeson regularized self- energy in one loop order, which is consistently with the Breit-Wigner distribution, converging to values of mass and width of this scalar resonance given in the experimental results reported by the E791 Collaboration at Fermilab and BES Collaboration at the Beijing Electron Positron Collider. We conclude that the sigma meson mass is restricted to be on the range 453MeV < mσ< 490MeV and its width 238MeV-354MeV or 354MeV < mσ< 415MeV and its width 167.5 < Γσ< 347MeV MeV.

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arXiv2010

Statistical analysis of the sigma meson considered as two-pion resonance

It was found that the most simple analysis in the linear σ- model, where the sigma meson couples in vacuum to two virtual pions, predicted the most typical values for the σ-mass and total decay width as 486+/-7MeV and 340+/-20MeV respectively. It was demonstrate, via statistical analysis, that the experimental values reported by the Fermilab (E791) Collaboration represents approximately 56% of the values predicted by the linear σ- model together with the Breit-Wigner formalism. Additional, it was created the spectral function, in terms of the σ-meson regularized self-energy, which is consistently with the Breit-Wigner distribution and it reproduces reasonably well the total width and observable mass given by the Fermilab (E791) Collaboration and Dalitz plot. The results are a strong evidence that the σ- meson can be considered as a two-pion resonance.

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