Topics on Hadron Collider Physics

Abstract

In this dissertation we present four techniques that could be used at the Large Hadron Collider (LHC) to improve the efficiency with which collected data is utilized, and to help detect signals of physics beyond the Standard Model. We present an extension of the Qjets algorithm which allows us to exploit the different possibilities for reconstructing an event at the LHC to produce multiple interpretations for each event. For example, using this approach on a Higgs plus Z boson sample, with h → bb we find a 28% improvement in significance can be realized at the 8 TeV LHC. We also propose a measurement of the bottom quark forward-central asymmetry at the LHC in order to gain further insight into the Tevatron t tbar anomaly. Using a toy axigluon model we find that if the relevant new-physics couplings to the bottom quark are similar to those of the top, then the effects should be visible at the 2 σ level in less than 10 fb-1 of 7 TeV LHC data. Finally we develop two techniques to measure fundamental quantum numbers of new particles at the LHC, with the goal of distinguishing between different theories beyond the Standard Model. In the first case we consider long lived colored particles and in the second case we consider bound states of new colored particles which annihilate into Standard Model particles.