Master of Science (MS)
Physics and Astronomy
Neutrinos are a useful tool that serves as an immediate probe of the Sun’s core providing insight into the details of the Sun’s energy production, internal composition and structure. Across the globe a number of solar neutrinos experiments have helped to clarify various characteristics of the solar neutrino spectrum. However, little experimental information is known regarding low-energy solar neutrinos, which comprise about 90% of the total solar neutrino spectrum. With this in mind, we are developing the Low Energy Solar Neutrino Spectrometer (LENS), an indium-based liquid scintillator detector with the capability to precisely measure the full spectrum of solar neutrinos, including pp, 7Be, pep, and CNO neutrinos, through the charged current reaction. Due to the high sensitivity required to detect low energy neutrinos, the LENS concept must aim for precise time and spatial correlations. This is to be accomplished using a highly segmented optical lattice architecture, where total internal reflection of light produces excellent spatial resolution. A program of R&D is being conducted to test the future performance of the LENS detector technology. This thesis focuses on construction and testing of the first prototype, μLENS, a small-scale detector prototype with 110 liters of Linear alkylbenzene (LAB) scintillator designed to test construction techniques and light transport in the scintillation lattice architecture. A number of measurements with the μLENS prototype were performed. We studied light channeling inside the detector by illuminating it with external radioactive sources. The patterns of light reaching the outer surface of the μLENS were measured with an array of photomultipliers. A data acquisition system and analysis codes were developed to collect and process the data. The γ background rates inside the Kimballton Underground Research Facility (KURF) were also studied using a NaI detector and the μLENS prototype. We also performed a test of light transport with external LEDs. The next step in the development of LENS is construction of miniLENS, a next generation prototype detector that will include external shielding to probe the absolute sensitivity of the LENS concept at neutrino rates.
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Afanasieva, Liudmyla, "Study of the low energy solar neutrino spectrometer (LENS) concept with the uLENS prototype" (2014). LSU Master's Theses. 848.