Information on Lagrangian parameters (Higgs basis)

Scalar potential parameters

All quartic terms parameters must be given, all the masses terms parameters (mu1, mu2 and mu3) being fixed by the minimization constraints. Lambda1 to lambda4 are real parameters. Lambda5 could be in general a complex parameter but since only the phase differences between lambda5, lambda6, lambda7 and mu3 matter, the phase of lambda5 can always be rotated out. We will thus consider it as a real parameter here while lambda6 and lambda7 are a priori complex.

Yukawa couplings parameters

Yukawa couplings must be given in the physical basis, i.e. in the basis where the M matrix is diagonal. Since in the Higgs basis only the first Higgs doublet gets a non zero vev, the M matrix is completely fixed by observed fermion masses while the Y matrix (giving the couplings of the second Higgs doublet) is a priori free. For this matrix, the first indice refers to doublet generation while the second one refer to the singlet generation. For example, Y2B stands for the complex Yukawa couplings of the second Higgs doublet to the second generation quark left doublet and to the bottom singlet.

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