Feasibility of reconstructing ttH (with H decaying to WW) for the purpose of measuring the Standard Model Higgs CP
This work investigates the feasibility of reconstructing ttH (with H decaying to WW) for the purpose of measuring the Standard Model Higgs CP. The method used to measure the Higgs CP relies on using the top quark momenta and therefore requires that the ttH topology be fully reconstructed. To this end, a fit based method using chi squared minimization is implemented and explored as a means by which the events can be reconstructed. This method is compared to a multivariate boosted decision tree implementation. The boosted decision tree implementation yields improved results compared to the fit based approach, particularly in events with a semi-leptonically decaying top. In such events, this approach is seen to yield improvements of the order of 10 % for certain aspects of the reconstructed topology and by as much as a few percent for the ttH topology as a whole.