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Discriminating between effective theories of U_{A}(1) symmetry breaking

V. Dmitrasinovic
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Abstract

We address the question if one can empirically distinguish between the two proposed solutions to the ``$U_A (1)$ problem'': the 't Hooft, and the Veneziano-Witten $U_{A}(1)$ symmetry breaking effective interactions. Two hadronic observables are offered as discriminants: (1) The scalar ($0^{+}$) meson spectrum; (2) Weinberg's second spectral sum rule. Their present experimental status is discussed.

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V. Dmitrasinovic. 2001-05-17. Discriminating between effective theories of U_{A}(1) symmetry breaking. https://doi.org/10.1063/1.1425488

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