Measurement of energy density as a function of pseudorapidity in proton-proton collisions at √s= 13 TeV with the cms experiment at the LHC

In this thesis, measurement of energy density is presented using data which taken through the Compact Muon Solenoid (CMS) detector in proton-proton collision for center of mass energy of √s = 13 TeV. The data have been collected at low luminosity in 2015 without magnetic field. The energy density as well as transverse energy density measurements within the pseudorapidity ranges of 3.15 <|eta|<5.2 and -6.6< eta<-5.2 is performed. The data used in this analysis were also compared with the data collected with magnetic field at the same energy. The results obtained from analysis and prediction of models that describe high-energy hadronic interactions are compared with each other. All models considered suggest a different form of the pseudorapidity dependence for the energy density compared to that observed in the data. An additional comparison is made with earlier proton-proton collision data at √s = 0.9 TeV and √s = 7 TeV which allows to test the hypothesis of limiting fragmentation.