University of Louisville
A Study of Beampipe Background Using Bhabha Events
Institution
University of Louisville
Faculty Advisor/ Mentor
David Brown
Abstract
Spurious protons from beampipe interactions are known to contaminate high energy electron-positron scattering and annihilation events. This forms a serious background to studies of particle decay modes involving baryons. In this project, we examine data from the BaBar Experiment at the Stanford Linear Accelerator Center. Bhabha events (e+ e- Æ e+e-), in which either of the outgoing particles interacts inelastically with the beampipe, provide a kinetically well-tagged data sample useful for characterizing the proton background. We select candidate events using a set of global and local cuts. We find that the candidate events comprise 1.12% of all events triggered in the detector. From the candidate set we characterize the nature and extent of proton contamination in generic events.
A Study of Beampipe Background Using Bhabha Events
Spurious protons from beampipe interactions are known to contaminate high energy electron-positron scattering and annihilation events. This forms a serious background to studies of particle decay modes involving baryons. In this project, we examine data from the BaBar Experiment at the Stanford Linear Accelerator Center. Bhabha events (e+ e- Æ e+e-), in which either of the outgoing particles interacts inelastically with the beampipe, provide a kinetically well-tagged data sample useful for characterizing the proton background. We select candidate events using a set of global and local cuts. We find that the candidate events comprise 1.12% of all events triggered in the detector. From the candidate set we characterize the nature and extent of proton contamination in generic events.