UC Riverside

One of the important early searches at the Large Hadron Collider at CERN is for high mass Z-like objects. Such objects are predicted in a number of extensions to the Standard Model and the analyses may become sensitive to their decays at fairly modest integrated luminosities. This thesis decribes a search for a neutral, heavy gague boson decaying into boosted top quark pairs using the first 5.0 fb-1 of sqrt(s) = 7 TeV data from the 2011 physics run of the LHC. By exploiting the semi-muonic decays of the top pairs and using boosted decision trees to perform the final event selection we set upper limits on the cross section of a heavy, Z-like gague boson of 5 pb at the lowest masses (500 GeV) to less than 1 pb for masses above 1 TeV.