Queen's 2015 Nobel Prize in PhysicsAustin de St. Croix has successfully defended his PhD thesis. His thesis title is "Light Detection and Production in Scintillating Liquid Detectors". He conducted his research under the supervision of Prof. Ken Clark.
Humans study the universe. Why? Because we must know. Liquid argon and xenon detectors play a central role in the search for dark matter, and the study of neutrinos. Measuring scintillation light is a critical step in the detection process, with silicon photomultipliers (SiPMs) the technology of choice. This thesis first describes and validates an analytic model describing SiPM photon detection efficiency (PDE), giving predictive power and improving simulation accuracy. Next, the (unwanted) emission of photons from a SiPM is characterized in a liquid xenon detector (ExCT). Lastly, the scintillation efficiency of liquid CF4 is reported for the first time. For gammas, the yield is roughly 4 photons/keV, which may benefit the Scintillating Bubble Chamber experiment. This work also includes tidbits on the scintillation process and localized heat production as it pertains to bubble nucleation.
