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Lagrangian

Lagrangian

For a realistic model, in particular a SUSY model, the Lagrangian is generally very lengthy. Therefore, SARAH splits it in different parts in order to speed up some calculations. This splitting might be also helpful for analyzing the structure of interactions involving different kinds of fields. SARAH saves the different parts of the Lagrangian for the different eigenstates in the following variables:

  • LagSV[$EIGENSTATES]: Parts with scalars and vector bosons (= kinetic terms for scalars)
  • LagFFV[$EIGENSTATES]: Parts with fermions and vector bosons (= kinetic terms of scalars)
  • LagSSSS[$EIGENSTATES]: Parts with only scalars (= scalar potential)
  • LagFFS[$EIGENSTATES]: Parts with fermions and scalars
  • LagVVV[$EIGENSTATES]: Parts with three vector bosons
  • LagVVVV[$EIGENSTATES]: Parts with four vector bosons
  • LagGGS[$EIGENSTATES]: Parts with ghosts and scalars
  • LagGGV[$EIGENSTATES]: Parts with ghosts and vector bosons
  • LagSSA[$EIGENSTATES]: Parts with scalars and auxiliary fields (only needed for CalcHep output)

In addition, for an effective theory, there might exist

  • LagSSSSSS[$EIGENSTATES]: Dimension 6 operators with only scalars
  • LagSSSVVV[$EIGENSTATES]: Dimension 6 operators with scalars and fermions
  • LagFFFF[$EIGENSTATES]: Dimension 6 operators with only fermions
  • LagFFSS[$EIGENSTATES]: Dimension 5 operators with fermions and scalars
  • LagFFVV[$EIGENSTATES]: Dimension 6 operators with fermions and vector bosons

Moreover, the different results of the calculation of the Lagrangian in gauge eigenstates are also saved separately. The variable names are:

  • Superpotential: Superpotential
  • Fermion - scalar interactions coming from the superpotential: Wij
  • F-Terms: FTerms
  • Scalar soft-breaking masses: SoftScalarMass
  • Gaugino masses: SoftGauginoMass
  • Soft-breaking couplings: SoftW
  • Kinetic terms for scalars: KinScalar
  • Kinetic terms for fermions: KinFermion
  • D-Terms: DTerms
  • Interactions between gauginos and a scalar and a fermion: FSGaugino
  • Trilinear self-interactions of gauge bosons: GaugeTri
  • Quartic self-interactions of gauge bosons: GaugeQuad
  • Interactions between vector bosons and gauginos: BosonGaugino

Furthermore, the additional interactions and the redefinition of existing interactions are saved in LagRedefinition.

See also