We have performed a dynamical analysis of the mixing in the pseudoscalar channel with the goal of understanding the existence and behavior of the pseudoscalar glueball. Our philosophy has not been to predict precise values of the glueball mass but to exploit an adequate effective theory to the point of breaking and to analyze which kind of mechanisms restore compatibility with data. Our study has led to analytical solutions which allow a clear understanding of the phenomena. The outcome of our calculation leads to a large mass glueball M-Theta > 2000 MeV, to a large glue content of the eta ', and to mixing angles in agreement with previous numerical studies.

We thank H.-Y. Cheng, C. Degrande, R. Escribano, J.-M. Gérard, N. Kochelev and H.-N. Li for valuable comments regarding this manuscript. V.M. thanks the Departamento de Física Teórica of Valencia for the hospitality and the I.I.S.N. for financial support. This work was supported in part by HadronPhysics2, a FP7-Integrating Activities and Infrastructure Program of the European Commission under Grant 227431, by the MICINN (Spain) grant FPA2007-65748-C02- and by GVPrometeo2009/129. We thank the authors of Jaxo- Draw for making drawing diagrams an easy task.

Peer reviewed