We present an overview of the status and recent developments of FeynHiggs (current version: 2.14.3) since version 2.12.2. The main purpose of FeynHiggs is the calculation of the Higgs-boson masses and other physical observables in the MSSM. For a precise prediction of the Higgs-boson masses for low and high SUSY scales, state-of-the-art fixed-order and effective-field-theory calculations are combined. We first discuss improvements of the fixed-order calculation, namely an optional DR renormalization of the stop sector and a renormalization of the Higgs sector ensuring the chosen input mass to be equivalent with the corresponding physical mass. Second, we describe improvements of the EFT calculation, i.e. an implementation of non-degenerate threshold corrections as well as an interpolation for complex parameters. Lastly, we highlight some improvements of the code structure easing future extensions of FeynHiggs to models beyond the MSSM.Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 1426 Does the new version supersede the previous version? Yes.Reasons for the new version: Improved calculations and code structure. Summary of revisions:Apart from improvements discussed in other publications: implementation of optional DR renormalization of stop sector, adapted two-loop Higgs sector renormalization, implementation of full non-degenerate threshold corrections, interpolation of EFT calculation for complex parameters, better code structure.Nature of problem: The Minimal Supersymmetric Standard Model (MSSM) allows predictions for the masses and mixings of the Higgs bosons in terms of a few relevant parameters. Therefore, comparisons to experimental data provide constraints on the parameter space. To fully profit from the experimental precision, a comparable level of precision is needed for the theoretical prediction.Solution method: State-of-the-art fixed-order and effective-field-theory calculations are combined to obtain a precise prediction for small as well as large supersymmetry scales.

Results for the leading two-loop corrections of O α 2 t from the Yukawa sector to the Higgs-boson mass spectrum of the MSSM with complex parameters are presented, with details of the analytical calculation performed in the Feynman-diagrammatic approach using a mixed on-shell DR scheme that can be directly matched onto the higher-order terms in the code FeynHiggs. Numerical results are shown for the masses and mixing effects in the neutral Higgs-boson sector and their variation with the phases of the complex parameters. Furthermore, the analytical expressions of the two-loop self-energies and the required renormalization constants are recorded. The new results can consistently be implemented in FeynHiggs.

Results for the leading two-loop corrections of O α 2 t from the Yukawa sector to the Higgs-boson masses of the MSSM with complex parameters are presented. The corresponding self-energies and their renormalization have been obtained in a Feynman-diagrammatic approach. A numerical analysis of the new contributions is performed for the mass of the lightest Higgs boson, supplemented by the full one-loop result and the O(α t α s ) terms including complex phases. In the limit of the real MSSM a previous result is confirmed.The discovery of a new boson [1, 2] with a mass around 125.6 GeV by the experiments ATLAS and CMS at CERN has triggered an intensive investigation to reveal the nature of this particle as a Higgs boson from the mechanism of electroweak symmetry breaking. Within the present experimental uncertainties, which are still considerably large, the measured properties of the new boson are consistent with the corresponding predictions for the Standard Model Higgs boson [3], but still a large variety of other interpretations is possible which are connected to physics beyond the Standard Model. Within the theoretical well motivated minimal supersymmetric Standard Model (MSSM), the observed particle could be classified as a light state within a richer predicted spectrum. The Higgs sector of the MSSM consists of two complex scalar doublets leading to five physical Higgs bosons and three (would-be) Goldstone bosons. At the tree-level, the physical states are given by the neutral CP -even h, H and CP -odd A bosons, together with the charged H ± bosons, and can be parametrized in terms of the A-boson mass m A and the ratio of the two vacuum expectation values, tan β = v 2 /v 1 . In the MSSM with complex parameters, the cMSSM, CP violation is induced in the Higgs sector by loop contributions with complex parameters from other SUSY sectors leading to mixing between h, H and A in the mass eigenstates [4].Masses and mixings in the neutral sector are sizeably influenced by loop contributions, and accordingly intensive work has been invested into higher-order calculations of the mass spectrum from the SUSY parameters, in the case of the real MSSM [5][6][7][8][9][10][11][12][13][14][15][16] as well as the cMSSM [17][18][19][20]. The largest loop contributions arise from the Yukawa sector with the large top Yukawa coupling h t , or α t = h 2 t /(4π), respectively. The class of leading two-loop Yukawa-type corrections of O α 2 t has been calculated so far only in the case of real parameters [11,12], applying the effective-potential method. Together with the full one-loop result [21] and the leading O(α t α s ) terms [20], both accomplished in the Feynman-diagrammatic approach including complex parameters, it has been implemented in the public program FeynHiggs [7,13,[21][22][23]. A calculation of the O α 2 t terms for the cMSSM, however, has been missing until now.In this letter we present this class of O α 2 t contributions extended to the case of complex parameters. The computation has been carried out in the Feynman-diagr...