FlexibleSUSY 2.0: Extensions to investigate the phenomenology of SUSY and non-SUSY models

Peter Athron, Markus Bach, Dylan Harries, Thomas Kwasnitza, Jae hyeon Park, Dominik Stöckinger, Alexander Voigt, Jobst Ziebell

Research output: Contribution to journalArticleResearchpeer-review

68 Citations (Scopus)


We document major new features and improvements of FlexibleSUSY, a Mathematica and C++ package with a dependency on the external package SARAH, that generates fast and precise spectrum generators. The extensions presented here significantly increase the generality and capabilities of the FlexibleSUSY package, which already works with a wide class of models, while maintaining an elegant structure and easy to use interfaces. The FlexibleBSM extension makes it possible to also create spectrum generators for non-supersymmetric extensions of the Standard Model. The FlexibleCPV extension adds the option of complex parameters to the spectrum generators, allowing the study of many interesting models with new sources of CP violation. FlexibleMW computes the decay of the muon for the generated model and thereby allows FlexibleSUSY to predict the mass of the W boson from the input parameters by using the more precise electroweak input of {GF,MZem} instead of {MW,MZem}. The FlexibleAMU extension provides a calculator of the anomalous magnetic moment of the muon in any model FlexibleSUSY can generate a spectrum for. FlexibleSAS introduces a new solver for the boundary value problem which makes use of semi-analytic expressions for dimensionful parameters to find solutions in models where the classic two-scale solver will not work such as the constrained E6SSM. FlexibleEFTHiggs is a hybrid calculation of the Higgs mass which combines the virtues of both effective field theory calculations and fixed-order calculations. All of these extensions are included in FlexibleSUSY 2.0, which is released simultaneously with this manual. Program summary: Program title: FlexibleSUSY Program Files doi: http://dx.doi.org/10.17632/kf7m8gn8vp.1 Licensing provisions: GPLv3 Programming language: C++, Wolfram/Mathematica, FORTRAN, Bourne shell Journal reference of previous version: Comput.Phys.Commun. 190 (2015) 139–172 Does the new version supersede the previous version?: Yes Reasons for the new version: Program extension including new models, observables and algorithms Summary of revisions: Extension to non-supersymmetric models (FlexibleBSM), complex parameters (FlexibleCPV), prediction of W boson mass from muon decay (FlexibleMW), calculation of anomalous magnetic moment of the muon (FlexibleAMU), semi-analytic boundary value problem solver (FlexibleSAS), improved hybrid Higgs mass calculation (FlexibleEFTHiggs). Nature of problem: Determining the mass spectrum, mixings and further observables for an arbitrary extension of the Standard Model, input by the user. The generated code must find simultaneous solutions to constraints that are specified at two or more different renormalization scales, which are connected by renormalization group equations forming a large set of coupled first-order differential equations. Solution method: Nested iterative algorithm and numerical minimization of the Higgs potential. Restrictions: The couplings must remain perturbative at all scales between the highest and lowest boundary condition. Tensor-like Lagrangian parameters of rank 3 are currently not supported. The automatic determination of the Standard Model-like gauge and Yukawa couplings is only supported for models that have the Standard Model gauge group SU(3)C×SU(2)L×U(1)Y as a gauge symmetry group factor. However, due to the modular nature of the generated code, adapting and extending it to overcome restrictions in scope is quite straightforward.

Original languageEnglish
Pages (from-to)145-217
Number of pages73
JournalComputer Physics Communications
Publication statusPublished - 1 Sep 2018


  • Higgs
  • Renormalization group equations
  • Sparticle
  • Supersymmetry

Cite this