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arXiv · 0809.1795

Two photon decays of scalar mesons in the quark NJL model

Yu. L. Kalinovsky·M. K. Volkov
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Abstract

Two photon decays of scalar mesons f_0(980), a_0(980), σ(600) in the quark Nambu - Jona - Lasinio (NJL) model are calculated. The contributions of the meson loops are taken into account along with the quark loops (Hartree - Fock approximation). This corresponds to the next order of the 1/N_c expansion, where N_c=3 is the number of quark colors. It is shown that the meson and quark loops give comparable contributions to the amplitude. Moreover, in the process f_0(980)-> γγthe kaon loop plays the dominant role. A similar situation takes place in the decay ϕ-> f_0(980) γ\cite{physrev}. Our results are in satisfactory agreement with the recent experimental data.

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Yu. L. Kalinovsky, M. K. Volkov. 2008-09-10. Two photon decays of scalar mesons in the quark NJL model. https://arxiv.org/abs/0809.1795

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