Quark - Resonance Model

We construct an effective Lagrangian for low energy hadronic interactions through an infinite expansion in inverse powers of the low energy cutoff Λχ of all possible chiral invariant non-renormalizable interactions between quarks and mesons degrees of freedom. We restrict our analysis to the leading terms in the 1/Nc expansion. The effective expansion is in (μ /Λχ) P ln(Λχ/μ 2)Q. Concerning the next-to-leading order, we show that, while the pure μ/Λχ corrections cannot be traced back to a finite number of non renormalizable interactions, those of order (μ/Λχ) ln(Λ 2 χ/μ 2) receive contributions from a finite set of 1/Λχ terms. Their presence modifies the behaviour of observable quantities in the intermediate Q2 region. We explicitely discuss their relevance for the two point vector currents Green’s function. ROM2F 93/37 December 93 ∗ email: [email protected] email: [email protected]