Strange Mesonic Transition Form Factor in the Chiral Constituent Quark Model

Abstract

The form factor $g_{ρπ}^{(S)}(Q^{2})$ of the strange vector current transition matrix element $<ρ| \bar{s}γ_\mus|π>$ is calculated within the chiral quark model. A strange vector current of the constituent $U$- and D-quarks is induced by kaon radiative corrections and this mechanism yields the nonvanishing values of $g_{ρπ}^{(S)}(0)$. The numerical result at the photon point is consistent with the one given by the $ϕ$-meson dominance model, but the fall-off in the $Q^{2}$-dependence is faster than the monopole form factor. Mesonic radiative corrections are also examined for the electromagnetic $ρ$-to-$π$ and $K^{*}$-to-$K$ transition amplitudes.