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arXiv · 0707.3594

On the spectral functions of scalar mesons

Francesco Giacosa·Giuseppe Pagliara
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Abstract

In this work we study the spectral functions of scalar mesons in one- and two-channel cases. When the propagators satisfy the Källen-Lehman representation a normalized spectral function is obtained, allowing to take into account finite-width effects in the evaluation of decay rates. In the one-channel case, suitable to the light sigma and k mesons, the spectral function can deviate consistently from a Breit-Wigner shape. In the two-channel case with one subthreshold channel the evaluated spectral function is well approximated by a Flatte' distribution; when applying the study to the a_0(980) and f_0(980) mesons the tree-level forbidden KK decay is analysed.

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Francesco Giacosa, Giuseppe Pagliara. 2007-07-25. On the spectral functions of scalar mesons. https://doi.org/10.1103/physrevc.76.065204

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