D+→K-π+π+: three-body FSI.

Even with the important advances of the last decade, charmed meson decays are still poorly understood theoretically. We do not understand, for example, why the kappa scalar resonance is responsible for 70% of the fit in the D+→K-π+π+ decay, as observed by the E791 (2002) experiment[1] and confirmed by different collaborations[2, 3]. The fact that quark c can neither be considered soft nor heavy prevents the direct use of known theoretical results in the description of D. This scenario indicates two big gaps in the knowledge of D+→π+π+K- decay. The first concerns the weak vertex, still not suitably treated in literature. The second is the three-body final state interaction (FSI) of the pseudoscalar mesons, until now considered in the literature as a quasi two-body interaction . This investigation aims at calculating the D+→π+π+K- decay considering 3 body FSI. [ABSTRACT FROM AUTHOR]