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arXiv · 1003.3493

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

M. C. Menchaca Maciel·J. R. Morones Ibarra
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Abstract

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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M. C. Menchaca Maciel, J. R. Morones Ibarra. 2010-03-17. Statistical analysis of the sigma meson considered as two-pion resonance. https://arxiv.org/abs/1003.3493

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