MSSMD Model

Author

Wei Shi

Rice University, weishi[at]rice.edu

Model Description

The model is based on MSSM, but adding a dark sector. The dark sector, U(1)D, is broken, giving rise to light dark photons (γD) that weakly couple to the SM particles via a small kinetic mixing with photons. The lightest neutralino n1 in MSSM is no longer stable and can decay via processes such as n1 → nD + γD, where nD is a light dark neutralino (fermion). In this model, the γD is mediated by very weak interactions with the SM, and can decay to muon pairs promptly or non-promptly.

References

​https://cds.cern.ch/record/2232052/files/HIG-16-035-pas.pdf

​https://link.springer.com/content/pdf/10.1007/JHEP05(2010)077.pdf

Model Files

MSSMD implementation: http://feynrules.irmp.ucl.ac.be/attachment/wiki/MSSMD/MSSMD.fr

Parameter file: http://feynrules.irmp.ucl.ac.be/attachment/wiki/MSSMD/sps1a.dat

Example of a notebook to produce UFO model: http://feynrules.irmp.ucl.ac.be/attachment/wiki/MSSMD/MSSMD.nb

UFO model: http://feynrules.irmp.ucl.ac.be/attachment/wiki/MSSMD/MSSMD_UFO.zip

Validation

The model is validated by checking kinematic distribution plots from the LHE file generated by MadGraph5.

​https://github.com/weishi10141993/DarkSUSY_MC_MG5/tree/master/MSSMDarkSector/MG5_0p25_cT_100_LHE

​https://github.com/weishi10141993/DarkSUSY_MC_MG5/tree/master/MSSMDarkSector/MG5_8p5_cT_100_LHE

Acknowledgement

The author would like to thank F. Elahi and M. Abdullah for helpful discussions. Thanks to B. Fuks for the help in the implementation. Thanks to O. Mattelaer for help interface with MadGraph5.