Distorted mass edges at LHC

Measuring mass and spin of new particles is of crucial importance for the understanding of general new physics models. We present two scenarios in which determination methods suffer from large uncertainties: the introduction of exotic particle content in B(MS)SM models as well as broadening effects due to off-shell contributions give rise to the distortion of kinematic distributions in an LHC environment. Consequently, this may not only affect determination of model parameters, but it can also impose a confusion with combinatorical effects of the underlying analysis. A correct treatment and modeling of these effects is thus indispensable for the ability to disentangle between different alternative BSM scenarios.