English

$\sigma(600)$ and background in $\pi\pi$ scattering

High Energy Physics - Phenomenology 2009-11-10 v2

Abstract

We suggest a simple analytical description of the S-wave isoscalar ππ\pi\pi amplitude, which corresponds to a joint dressing of the bare resonance and background contributions. The amplitude describes well the experimental data on the δ00\delta^0_0 phase shift in the energy region below 900 MeV and has two poles in the Res>0Re s > 0 half-plane. Besides the well-known pole of σ(600)\sigma(600)-meson with Resmπ2Re s \sim m_{\pi}^2, there exists a more distant pole with Res0.6GeV2Re s \sim 0.6 GeV^2. Our analysis indicates for the dynamical origin of the σ(600)\sigma(600) pole, while the second pole should be associated with lowest qqˉq\bar{q} state.

Keywords

Cite

@article{arxiv.hep-ph/0307063,
  title  = {$\sigma(600)$ and background in $\pi\pi$ scattering},
  author = {A. E. Kaloshin and V. M. Persikov and A. N. Vall},
  journal= {arXiv preprint arXiv:hep-ph/0307063},
  year   = {2009}
}

Comments

LaTeX2e, 11 pages with 7 figures;final version accepted in EPJ A

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