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Partial widths for the decays eta(1295) -> gamma gamma and eta(1440) -> gamma gamma

A. V. Anisovich·V. V. Anisovich·L. Montanet·V. A. Nikonov
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Abstract

We discuss gamma gamma partial widths of pseudoscalar/isoscalar mesons eta(M) in the mass region M = 1000-1500 MeV. The transition amplitudes eta(1295) -> gamma gamma and eta(1440) -> gamma gamma are studied within an assumption that the decaying mesons are the members of the first radial excitation nonet 2^1S_0 q\bar q. The calculations show that partial widths being of the order of 0.1 keV are dominantly due to the n\bar n meson component while the contribution of the s\bar s component is small.

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A. V. Anisovich, V. V. Anisovich, L. Montanet, V. A. Nikonov. 1999-10-13. Partial widths for the decays eta(1295) -> gamma gamma and eta(1440) -> gamma gamma. https://doi.org/10.1007/s100500050342

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