Desenvolvimento de um metodo alternativo para analise do Dalitz plot do canal $D^+ \to K^- K^+ \pi^+$

The violation of the charge conjugation and parity combined symmetry, or simply CP violation, is one of the necessary conditions to explain the matter-antimatter assymmetry. The Standard Model accommodates the CP violation through a phase in the CKM (Cabibbo-Kabayashi-Maskawa) matrix. However, this mechanism is not enough to explain the observed assymmetry. New sources of CP violation are necessary. Charm decays are excellent tools in the search of this new sources because the CP violation predicted by the Standard Model in charm decays is quite small, O(10−3) or less. One of the channels used in the search for CP violation is the Cabibbo suppressed $D^+ \to K^- K^+ \pi^+$ decay, exploiting the 2-dimensional phase space. The standard technique for study 3-body decays is the Dalitz plot analysis. It allows to study the decay dynamics, identifying its resonants contributions. It also allows, by comparing conjugate decays, the observation of local assymmetries in the phase space. The standard technique for Dalitz plot analysis is the fit with the maximum likelihood method. In the analysis of very large samples, it faces a practical problem once the number of events leads to an exponetial increase in the required processing time. An alternative may be the binned fit with least squares method. In this work, we developed an algorithm based in this method as an alternative to the one commonly used. It is made the comparison between this method and the maximum likelihood one, determining in which conditions both of them leads to the same result. This study is made with simulated samples of $D^+ \to K^- K^+ \pi^+$ decay.