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Glue content and mixing angle of the eta - eta' system. The effect of the isoscalar 0- continuum

N. F. Nasrallah
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Abstract

Masses and topological charges of the eta and eta' mesons are expressed in terms of the singlet-octet mixing angle theta. Contributions of the pseudoscalar 0- continuum are evaluated in a model independant way. Applications to the decay eta --> 3pi and to the radiative decay of vector mesons involving eta and eta' are considered. Agreement with experiment is in general good and the results quite stable for -30.5 <= theta <= -18.5

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N. F. Nasrallah. 2004-10-18. Glue content and mixing angle of the eta - eta' system. The effect of the isoscalar 0- continuum. https://doi.org/10.1103/physrevd.70.116001%2010.1103%2Fphysrevd.72.019903

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