Determination of $f_0-a_0^0$ mixing angle from QCD sum rules

Abstract

By assuming that the $f_0$ and $a_0^0$ mesons are mixed states of the two-quark - tetraquark, the mixing angle between them is estimated within QCD sum rules method, and it is obtained that the mixing angle is $(6.03\pm 0.08{)}^{\circ }$. Our prediction on mixing angle can be checked in further experiments which can shed light on choosing the "right" structure of $f_0$ and $a_0^0$ mesons.