A flexible parameterization of the CKM matrix via the singular-value-decomposition method

Abstract. We investigate a flexible method by which we can test the unitarity of the quark flavor-mixing matrix step by step. Singular-value-decomposition (SVD) techniques are used in analyzing the mixing matrix over a broader parameter region than the unitarity region. Unitary constraints let us extract CP-violating properties without any specific parameterization when the magnitudes of at least three mixing-matrix elements in three-generation quark mixing are given. This method can al so be applied to the analysis of lepton flavor mixing, in which only a few moduli are presently measured.