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arXiv · 0907.4234

LHC signature of supersymmetric models with non-universal sfermion masses

Abstract

We study the LHC signature of the minimal supersymmetric standard model with non-universal sfermion masses. In the model, soft masses of gauginos and the 3rd generation of 10 of SU(5) are around the weak scale, while other sfermion soft mass is universal and around a few TeV. Such sfermion mass spectrum is motivated not only from flavor, CP and naturalness constraints but also from E_6 grand unified model with non-Abelian horizontal (flavor) symmetry. The characteristic signature of the model at the LHC is the dominance of the events with 4 b partons in the final state together with high rate of mildly boosted top quark arising from gluino decay. The prominent high p_T jet also arises from squark decay. We show it is possible to find the characteristic signature in the early stage of the LHC. The discrimination of our scenario from some CMSSM model points with similar signature may be possible with large integrated luminosity. The result of sparticle mass measurement using exclusive channel with the help of hemisphere analysis, and inclusive measurement of gluino and squark masses using M_{T2} and M_{T2}^{min} in some representative model points are presented.

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Sung-Gi Kim, Nobuhiro Maekawa, Keiko I. Nagao, Mihoko M. Nojiri, Kazuki Sakurai. 2009-08-30. LHC signature of supersymmetric models with non-universal sfermion masses. https://doi.org/10.1088/1126-6708/2009/10/005

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