We describe the implementation of the renormalized complex MSSM (cMSSM) in the diagram generator FeynArts and the calculational tool FormCalc. This extension allows to perform UV-finite one-loop calculations of cMSSM processes almost fully automatically. The Feynman rules for the cMSSM with counterterms are available as a new model file for FeynArts. Also included are default definitions of the renormalization constants; this fixes the renormalization scheme. Beyond that all model parameters are generic, e.g. we do not impose any relations to restrict the number of input parameters.The model file has been tested extensively for several non-trivial decays and scattering reactions. Our renormalization scheme has been shown to give stable results over large parts of the cMSSM parameter space.

We evaluate two-body decay modes of neutralinos in the Minimal Supersymmetric Standard Model with complex parameters (cMSSM). Assuming heavy scalar quarks we take into account all two-body decay channels involving charginos, neutralinos, (scalar) leptons, Higgs bosons and Standard Model gauge bosons. The evaluation of the decay widths is based on a full one-loop calculation including hard and soft QED radiation. Of particular phenomenological interest are decays involving the Lightest Supersymmetric Particle (LSP), i.e. the lightest neutralino, or a neutral or charged Higgs boson. For the chargino/neutralino sector we employ two different renormalization schemes, which differ in the treatment of the complex phases. In the numerical analysis we concentrate on the decay of the heaviest neutralino and show the results in the two different schemes. The higher-order corrections of the heaviest neutralino decay widths involving the LSP can easily reach a level of about 10−15%, while the corrections to the decays to Higgs bosons are up to 20−30%, translating into corrections of similar size in the respective branching ratios. The difference between the two schemes, indicating the size of unknown two-loop corrections, is less than O(0.1%). These corrections are important for the correct interpretation of LSP and Higgs production at the LHC and at a future linear e + e − collider. The results will be implemented into the Fortran code FeynHiggs. * email: Aoife.Bharucha@desy.de † Former address The chargino/neutralino sector of the cMSSMWhile many details about the renormalization of the cMSSM can already be found in Refs. [37,38,45,46], we repeat here the most relevant aspects in order to give a complete picture and to facilitate the comparison between the two employed renormalization schemes. The chargino/neutralino sector contains two soft SUSY-breaking gaugino mass parameters M 1 and M 2 corresponding to the bino and the wino fields, respectively, as well as the Higgs superfield mixing parameter µ, which, in general, can be complex. Since not all the possible phases of the cMSSM Lagrangian are physical, it is possible (without loss of generality) to choose some parameters real. This applies in particular to one out of the three parameters M 1 , M 2 , and M 3 , the gluino mass parameter. For the numerical analysis in Sec. 4 we choose M 2 to be real, however for the renormalization scheme I introduced below [45,46], we do not make such an assumption, and the analytical derivation of the renormalization constants is performed for a complex M 2 , discussed further in Sec. 4.The starting point for the renormalization procedure of the chargino/neutralino sector is the part of the Fourier transformed MSSM Lagrangian which is bilinear in the chargino and neutralino fields,

We evaluate two-body decay modes of charginos in the Minimal Supersymmetric Standard Model with complex parameters (cMSSM). Assuming heavy scalar quarks we take into account all decay channels involving charginos, neutralinos, (scalar) leptons, Higgs bosons and Standard Model gauge bosons. The evaluation of the decay widths is based on a full one-loop calculation including hard and soft QED radiation. Special attention is paid to decays involving the Lightest Supersymmetric Particle (LSP), i.e. the lightest neutralino, or a neutral or charged Higgs boson. The higher-order corrections of the chargino decay widths involving the LSP can easily reach a level of about ±10%, while the corrections to the decays to Higgs bosons are slightly smaller, translating into corrections of similar size in the respective branching ratios. These corrections are important for the correct interpretation of LSP and Higgs production at the LHC and at a future linear e + e − collider. The results will be implemented into the Fortran code FeynHiggs. * email: Sven.Heinemeyer@cern.ch †

We re-assess the exclusion limits on the parameters describing the supersymmetric (SUSY) electroweak sector of the MSSM obtained from the search for direct charginoneutralino production at the LHC. We start from the published limits obtained for simplified models, where for the case of heavy sleptons the relevant branching ratio, BR(χ 0 2 →χ 0 1 Z), is set to one. We show how the decay modeχ 0 2 →χ 0 1 h, which cannot be neglected in any realistic model once kinematically allowed, substantially reduces the excluded parameter region. We analyze the dependence of the excluded regions on the phase of the gaugino soft SUSY-breaking mass parameter, M 1 , on the mass of the light scalar tau, mτ 1 , on tan β as well as on the squark and slepton mass scales. Large reductions in the ranges of parameters excluded can be observed in all scenarios. The branching ratios of charginos and neutralinos are evaluated using a full NLO calculation for the complex MSSM. The size of the effects of the NLO calculation on the exclusion bounds is investigated. We furthermore assess the potential reach of the experimental analyses after collecting 100 fb −1 at the LHC running at 13 TeV. * email: Aoife.Bharucha@desy.de † email: Sven.Heinemeyer@cern.ch ‡ email: pahlen@ifca.unican.es § MultiDark Fellow 1 With LHCx we denote the LHC running at √ s = x TeV.

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