Searches for Supersymmetry with the CMS Detector

Exclusion regions in a SUSY theory; source: CMS/CERN

Supersymmetry (SUSY) is a well motivated extension of the Standard Model (SM), introducing a new fundamental symmetry between fermions and bosons. As a consequence new particles (the SUSY partners of the SM particles) are predicted. The new particle content leads to a set of attractive features, as for example: a) In many scenarios, SUSY provides with the lightest SUSY particle (LSP) a prefect candidate for Dark Matter, a exotic form of matter which is ~5 time more abundant in the universe than ordinary matter. b) In the SM radiative corrections to the Higgs mass diverge, and therefore unnatural cancellations have to occur to stabilize the Higgs mass. In SUSY these cancellations are automatically incorporated c) In Grand Unified Theories the gauge couplings are expected to unify at a very high energy scale (~10E16 GeV). While in the SM the running couplings of the strong, the weak and the electromagnetic force do not meat in one point, they do meet in SUSY models.

As SUSY particles are not observed up to now, they have to be much heavier than the SM particles, and thus SUSY is a broken symmetry. The LSP is in many SUSY scenarios only weakly interacting, and if produced in proton-proton collisions it will escape the detector undetected. This leads to an imbalance of the events in the transverse momentum as a striking signature. The LHC and its experiments offers a huge potential for finding these hints of these signatures. With the CMS experiment at the LHC we are searching in various final states for SUSY particles, but also for other extensions of the SM.