Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.

The nonextensivity parameter q occurring in some of the applications of Tsallis statistics (known also as index of the corresponding Levy distribution) is shown to be given, in the q>1 case, entirely by the fluctuations of the parameters of the usual exponential distribution.

Abstract. We review from the point of view of nonextensive statistics the ubiquitous presence in elementary and heavy-ion collisions of power-law distributions. Special emphasis is placed on the conjecture that this is just a reflection of some intrinsic fluctuations existing in the hadronic systems considered. These systems summarily described by a single parameter q playing the role of a nonextensivity measure in the nonextensive statistical models based on Tsallis entropy.PACS. 89.75.-k complex systems -24.60.-k statistical theory and fluctuations -25.75.Dw particle production (relativistic collisions) -25.75.-q relativistic heavy ions collision