We have calculated the leading Yukawa corrections to the chargino, neutralino and gluino pole masses in the DR-bar scheme in the Minimal Supersymmetric Standard Model (MSSM) with the full set of complex parameters. We have performed a numerical analysis for a particular point in the parameter space and found typical corrections of a few tenths of a percent thus exceeding the experimental resolution as expected at the ILC. We provide a computer program which calculates two-loop pole masses for SUSY fermions with complex parameters up to the respective order in pertubation theory.
We have calculated the two-loop strong interaction corrections to the chargino pole masses in the DRbar-scheme in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters. We have performed a detailed numerical analysis for a particular point in the parameter space and found corrections of a few tenths of a percent. We provide a computer program which calculates chargino and neutralino masses with complex parameters including the one-loop corrections and all two-loop SQCD effects.
We have calculated the two-loop strong interaction corrections to the neutralino pole masses in the DRbar-scheme in the Minimal Supersymmetric Standard Model (MSSM). We have performed a detailed numerical analysis for a particular point in the parameter space and found corrections of a few tenths of a percent. We agree with previously derived analytic formulae for two-loop corrections to fermion masses.
We compute the two-loop O(as*at) corrections to the Higgs boson masses in supersymmetric extensions of the Standard Model with Dirac gaugino masses. We rely on the effective-potential technique, allow for both Dirac and Majorana mass terms for the gluinos, and compute the corrections in both the DRbar and on-shell renormalisation schemes. We give detailed results for the MDGSSM and the MRSSM, and simple approximate formulae valid in the decoupling limit for all currently-studied variants of supersymmetric models with Dirac gluinos. These results represent the first explicit two-loop calculation of Higgs boson masses in supersymmetric models beyond the MSSM and the NMSSM.
We compute the two-loop QCD corrections to the neutral Higgs-boson masses in the MSSM, including the effect of non-vanishing external momenta in the self-energies. We obtain corrections of O(alpha_t*alpha_s) and O(alpha*alpha_s), i.e., all two-loop corrections that involve the strong gauge coupling when the only non-vanishing Yukawa coupling is the top one. We adopt either the DRbar renormalization scheme or a mixed OS-DRbar scheme where the top/stop parameters are renormalized on-shell. We compare our results with those of earlier calculations, pointing out an inconsistency in a recent result obtained in the mixed OS-DRbar scheme. The numerical impact of the new corrections on the prediction for the lightest-scalar mass is moderate, but already comparable to the accuracy of the Higgs-mass measurement at the LHC.
Results are presented for the momentum dependent two-loop contributions of O(alpha_t alpha_s) to the masses and mixing effects in the Higgs sector of the MSSM. They are obtained in the Feynman-diagrammatic approach using a mixed on-shell/DRbar renormalization that can directly be matched onto the higher-order corrections included in the code FeynHiggs. The new two-loop diagrams are evaluated with the program SecDec. The combination of the new momentum dependent two-loop contribution with the existing one- and two-loop corrections in the on-shell/DRbar scheme leads to an improved prediction of the light MSSM Higgs boson mass and a correspondingly reduced theoretical uncertainty. We find that the corresponding shifts in the lightest Higgs-boson mass M_h are below 1 GeV in all scenarios considered, but can extend up to the level of the current experimental uncertainty. The results are included in the code FeynHiggs.