2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/48651We present the recent investigation of the $ΔS = 1$ effective weak chiral Lagrangian within the framework of the instanton-induced chiral quark model. Starting from the effective four-quark operators, we derive the effective weak chiral action by integrating out the constituent quark fields. Employing the derivative expansion, we obtain the effective weak chiral Lagrangian to ${\cal O} (p^4)$ order with low energy constants.Talk given at the 1998 YITP Workshop on QCD and Hadron Physics, 14-16 October, Kyoto, Japan. 5 pages with 1 figureHigh Energy Physics - Phenomenologytext