Uncertainties and Discovery Potential in Planned Experiments

We describe a method for estimation of the discovery potential on new physics in planned experiments. The effective significance of signal for given probability of observation is proposed for planned experiments instead of the usual significances S_1 = n_s/sqrt{n_b} and S_2 = n_s/sqrt{n_s+n_b}, where n_s and n_b are the average numbers of signal and background events. Application of the test of equal-probability allows to estimate the exclusion limits on new physics. We also estimate the influence of systematic uncertainty related to nonexact knowledge of signal and background cross sections on the discovery probability of new physics in planned experiments. An account of such systematics is very essential in the search for supersymmetry at LHC.