%0 Journal Article %T Dispersive Approach to Abelian Axial Anomaly and $\eta-\eta'$ Mixing %A Klopot %A Y. N. %A Oganesian %A A. G. %A Teryaev %A O. V. %J High Energy Physics - Phenomenology %D 2008 %I %X We investigate what can be learnt about the $\eta$ -$\eta'$ mixing by means of dispersive representation of axial anomaly. We show that our method leads to the strong bounds for the $\eta-\eta'$ mixing angle: $\theta = -15.3^o \pm 1^o$. Moreover, our result manifests also a dramatic dependence of the width $\Gamma_{\eta\to 2\gamma}$ on the mixing angle $\theta$. This property explains how the relatively small mixing strongly effects the decay width. %U http://arxiv.org/abs/0810.1217