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This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, [Formula: see text] and to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals-scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.

We describe recent extensions of the program SPheno including flavour aspects, CP-phases, R-parity violation and low energy observables. In case of flavour mixing all masses of supersymmetric particles are calculated including the complete flavour structure and all possible CP-phases at the 1-loop level. We give details on implemented seesaw models, low energy observables and the corresponding extension of the SUSY Les Houches Accord. Moreover, we comment on the possiblities to include MSSM extensions in SPheno. Program SummaryProgram title: SPheno Program Obtainable from: http://projects.hepforge.org/spheno/ Programming language: F95 Computers for which the program has been designed: PC running under Linux, should run in every Unix environment Operating systems: Linux, Unix Keywords: Supersymmetry, renormalization group equations, mass spectra of supersymmetric models, Runge-Kutta, decays of supersymmetric particles, production Nature of problem: The first issue is the determination of the masses and couplings of supersymmetric particles in various supersymmetric models the R-parity conserved MSSM with generation mixing and including CP-violating phases, various seesaw extensions of the MSSM and the MSSM with bilinear Rparity breaking. Low energy data on Standard Model fermion masses, gauge couplings and electroweak gauge boson masses serve as constraints. Radiative corrections from supersymmetric particles to these inputs must be calculated. Theoretical constraints on the soft SUSY breaking parameters from a high scale theory are imposed and the parameters at the electroweak scale are obtained from the high scale parameters by evaluating the corresponding renormalization group equations. These parameters must be consistent with the requirement of correct electroweak symmetry breaking. The second issue is to use the obtained masses and couplings for calculating decay widths and branching ratios of supersymmetric particles as well as the cross sections for theses particles in electron positron annihilation. The third issue is to calculate low energy constraints in the B-meson sector such as BR(b → sγ), ∆M Bs , rare lepton decays, such as BR(µ → eγ), the SUSY contributions to anomalous magnetic moments and electric dipole moments of leptons, the SUSY contributions to the rho parameter as well as lepton flavour violating Z decays. Solution method: The renormalization connecting a high scale and the electroweak scale is calculated by the Runge-Kutta method. Iteration provides a solution consistent with with the multi-boundary conditions. In case of three-body decays and for the calculation of initial state radiation Gaussian quadrature is used for the numerical solution of the integrals. Restrictions: In case of R-parity violation the cross sections are not calculated. Running time: 0.2 second on a Intel(R) Core(TM)2 Duo CPU T9900 with 3.06GHz 1 porod@physik.uni-wuerzbzrg.de 2 fnstaub@physik.uni-wuerzbzrg.de Preprint submitted to ElsevierSeptember 27, 2011 IntroductionIn its orginal version SPheno had been ...

SARAH is a Mathematica package optimized for the fast, efficient and precise study of supersymmetric models beyond the MSSM: a new model can be defined in a short form and all vertices are derived. This allows SARAH to create model files for FeynArts/FormCalc, CalcHep/CompHep and WHIZARD/O'Mega. The newest version of SARAH now provides the possibility to create model files in the UFO format which is supported by MadGraph 5, MadAnalysis 5, GoSam, and soon by Herwig++. Furthermore, SARAH also calculates the mass matrices, RGEs and 1-loop corrections to the mass spectrum. This information is used to write source code for SPheno in order to create a precision spectrum generator for the given model. This spectrumgenerator-generator functionality as well as the output of WHIZARD and CalcHep model files have seen further improvement in this version. Also models including Dirac Gauginos are supported with the new version of SARAH, and additional checks for the consistency of the implementation of new models have been created. Reasons for the new version: SARAH provides with this version the possibility to create model files in the UFO format. The UFO format is supposed to become a standard format for model files which should be supported by many different tools in the future. Also models with Dirac gauginos weren't supported in earlier versions. Nature of problem: To use Madgraph for new models it is necessary to provide the corresponding model files which include all information about the interactions of the model. However, the derivation of the vertices for a given model and putting those into model files which can be used with Madgraph is usually very time consuming. Dirac gauginos are not present in the minimal supersymmetric standard model (MSSM) or many extensions of it. Dirac mass terms for vector superfields lead to new structures in the supersymmetric (SUSY) Lagrangian (bilinear mass term between gaugino and matter fermion as well as new D-terms) and modify also the SUSY renormalization group equations (RGEs). The Dirac character of gauginos can change the collider phenomenology. In addition, they come with an extended Higgs sector for which a precise calculation of the 1-loop masses hasn't happened so far. Solution method: SARAH calculates the complete Lagrangian for a given model whose gauge sector can be any direct product of SU(N) gauge groups. The chiral superfields can transform as any, irreducible representation with respect to these gauge groups and it is possible to handle an arbitrary number of symmetry Preprint submitted to Elsevier February 14, 2013 breakings or particle rotations. Also the gauge fixing are automatically added. Using this information, SARAH derives all vertices for a model. These vertices can be exported to model files in the UFO which is supported by Madgraph and other codes like GoSam, MadAnalysis or ALOHA. The user can also study models with Dirac gauginos. In that case SARAH includes all possible terms in the Lagrangian stemming from the new structures and can also calculate the ...

SARAH is a Mathematica package for studying supersymmetric models. It calculates for a given model the masses, tadpole equations and all vertices at tree-level. This information can be used by SARAH to write model files for CalcHep/CompHep or FeynArts/FormCalc. In addition, the second version of SARAH can derive the renormalization group equations for the gauge couplings, parameters of the superpotential and soft-breaking parameters at one-and two-loop level. Furthermore, it calculates the one-loop self-energies and the one-loop corrections to the tadpoles. SARAH can handle all N = 1 SUSY models whose gauge sector is a direct product of SU (N ) and U (1) gauge groups. The particle content of the model can be an arbitrary number of chiral superfields transforming as any irreducible representation with respect to the gauge groups.To implement a new model, the user has just to define the gauge sector, the particle, the superpotential and the field rotations to mass eigenstates. Nature of problem: A supersymmetric model is usually characterized by the particle content, the gauge sector and the superpotential. It is a time consuming way to obtain all necessary information for phenomenological studies from this basic ingredients. Solution method: SARAH calculates the complete Lagrangian for a given model whose gauge sector can be any direct product of SU(N) gauge groups. The chiral superfields can transform as any, irreducible representation with respect to these gauge groups and it is possible to handle an arbitrary number of symmetry breakings or particle rotations. Also the gauge fixing terms can be specified. Using this information, SARAH derives the mass matrices and Feynman rules at tree-level and generates model files for CalcHep/CompHep and FeynArts/FormCalc. In addition, it can calculate the renormalization group equations at one-and two-loop level and the one-loop corrections to the one-and two-point functions. Unusual features: SARAH just needs the superpotential and gauge sector as input and not the complete Lagrangian. Therefore, the complete implementation of new models is done in some minutes. Running time: Measured CPU time for the evaluation of the MSSM on an Intel Q8200 with 2.33GHz. Calculating the complete Lagrangian: 12 seconds. Calculating all vertices: 75 seconds. Calculating the oneand two-loop RGEs: 50 seconds. Calculating the one-loop corrections: 7 seconds. Writing a FeynArts file: 1 second. Writing a CalcHep/CompHep file: 6 seconds. Writing the LaTeX output: 1 second.The LHC has started its work and will hopefully find soon the first clues for physics beyond the standard model (SM). Supersymmetry (SUSY) is the most prominent and well studied extension of the SM. However, most studies were done in the context of the Minimal Supersymmetric Standard Model (MSSM) [1][2][3][4][5][6]. Therefore, many computer tools can handle the MSSM out of the box but it demands some effort to implement new models. Also the analytical expressions for all possible interactions, renormalization group equations or ...