Analysis of the b ₁ meson decay in local tensor bilinear representation

We explore the validity of vector meson dominance in the radiative decay of the b₁(1235) meson. In order to explain the violation of the vector meson dominance hypothesis in this decay process, we investigate a model where the b₁ meson strongly couples with the local current in tensor bilinear representation. The tensor representation is investigated in the framework of the operator product expansion and we found a low energy decay process that does not follow the usual vector meson dominance hypothesis. The ω-like intermediate meson state of quantum numbers I^G(J^PC) = 0⁻(1^{− −}) is found to have a nontrivial role in the decay process of the b₁ meson. The spectral structure of the ω-like state is found to be close to a π-ρ hybrid state, which provides a mechanism that evades the usual vector meson dominance hypothesis. Precise measurements of various decay channels of the b₁ meson are, therefore, required to unravel the internal structure of axial vector mesons.