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The Mixing Angle of the Lightest Scalar Nonet

Jose A. Oller
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Abstract

We show that the κ, a_0(980), σand the f_0(980) resonances constitute the lightest scalar nonet in three different and complementary ways. First, by establishing the continuous movement of the poles from the physical to a SU(3) limit. Second, by performing an analysis of the couplings of the scalar mesons to pairs of pseudoscalars and third, by analysing the couplings of the scalars with meson-meson SU(3) scattering eigenstates. Every of the last two methods agree that the mixing angle between the singlet and the octet I=0 states is θ= 19^o\pm 5 degrees, so that the σis mainly the singlet and the f_0(980) the isosinglet octet state.

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Jose A. Oller. 2003-06-03. The Mixing Angle of the Lightest Scalar Nonet. https://doi.org/10.1016/j.nuclphysa.2003.08.002

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