Undergraduate Honors Theses

Thesis Defended

Spring 2019

Document Type


Type of Thesis

Departmental Honors


Engineering Physics

First Advisor

John Cumalat


In particle physics, when a particle decays, it is not always possible to fully reconstruct the decaying particle. This is due to the nature that some particles, such as neutrinos, do not typically interact and go straight through the detector unnoticed. This means when attempting to reconstruct the original mass of the decay, there will be missing information. Thus, the question is, even when there is missing information in a decay, is it possible to accurately reconstruct the decaying particle? In this project we will be focusing on the decay of Z->TauhTauh, which will henceforth be referred to as a ditau decay, and the applicability of the reconstruction techniques discussed to other particles that undergo a ditau decay. This project focuses on the implementation of a new kinematic method for determining the momentum of a hadronically decaying 3-prong tau. Given this new way of determining the momentum, it has been tested on Monte Carlo samples before being run over data. What was found was that given this new technique, it is possible to reduce background contained in the reconstruction. This gives a higher signal significance for the ditau reconstruction. As signal significance is the figure of merit for discovery potential, this gives hope to the idea that the technique discussed will be able to be used on more than just Z decays.