Study of the electromagnetic transition form-factor in ω → π0μ+μ- decay

Sixty events of the rare electromagnetic decay ω → π0μ+μ- have been detected. The branching ratio for this decay been obtained to be BR(ω → π0μ+μ-) = (9.6 +- 2.3) x 10-5. The effective mass spectrum for muon pairs has been measured and the electromagnetic transition form-factor for the vertex ωπ0, Fω(m2sub(μ)sub(μ);m2sub(π)0) = (1-m2sub(μ)sub(μ)/Λ2)-1, has been determined, Λ = (0.65 +- 0.03) GeV/c2. The results are compared with the vector-meson dominance model. (orig.)