Exploring QCD uncertainties when setting limits on compressed supersymmetric spectra

If Supersymmetry (SUSY) has a compressed spectrum the current limits from the LHC can be drastically reduced. We take possible `worst case' scenarios where combinations of the stop, squark and gluino masses are degenerate with the mass of the lightest SUSY particle. To accurately derive limits in the model, care must be taken when describing QCD radiation and we examine this in detail. Lower mass bounds are then produced by considering all the 7 TeV hadronic SUSY and monojet searches. The evolution of the limits as the mass splitting is varied is also presented.

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