CAREER: Next-Generation Liquid Scintillator Detectors: Picosecond Timing and Quantum-Dot-Doped Scintillator

即使在十多年的伟大发现之后，中微子仍然是已知基本粒子中最神秘的。关于其性质的基本问题依然存在；最基本的问题是中微子是否是自身的反粒子。如果这是真的，中微子的这种马约拉纳性质将对粒子物理学和宇宙学产生深远的影响，包括对宇宙中物质-反物质不对称的解释。唯一可行的实验探测中微子的马约拉纳性质是实验寻找罕见的核过程，中微子双β衰变。目前的一组实验将探测反向质量层次中的马约拉纳中微子的参数空间。下一代实验将需要推进到正常的质量层次，这需要在质量和背景抑制方面增加一个数量级。液体闪烁体探测器可以很好地测量大质量，但需要改进以获得更大的背景抑制。该奖项将支持一项研究计划，该计划的重点是结合光电探测器的进步和使用纳米晶体形式的新型波长移位器，称为量子点，以从液体闪烁体探测器中提取方向信号。更广泛的影响：本科研究对招收和留住物理专业的学生至关重要。该奖项将用于改善转学生的机会。加州大学洛杉矶分校将举办一系列关于如何在物理专业取得成功的研讨会。该系列的修改版本也将在圣莫尼卡学院展出。此外，这笔拨款将在加州大学洛杉矶分校的本科生研究经验（REU）项目中提供一个额外的名额。

Even after more than a decade of great discoveries, the neutrino remains the most mysterious of the known fundamental particles. Basic questions about its properties endure; the most basic being whether the neutrino is its own antiparticle. If true, this Majorana nature of the neutrino would have profound implications to particle physics and cosmology, including an explanation for the matter-antimatter asymmetry in the universe. The only feasible experimental probes of the Majorana nature of the neutrino are experiments searching for the rare nuclear process, neutrinoless double-beta decay. The current set of experiments will probe the parameter space for Majorana neutrinos in the inverted mass hierarchy. The next generation of experiments will need to push into the normal mass hierarchy which requires an order of magnitude increase in mass and background suppression. Liquid scintillator detectors scale well to large masses but advances are needed to obtain increased background suppression. This award will support a program of research that focusses on combining advances in photodetectors and the use of novel wavelength shifters in the form of nanocrystals called quantum dots to extract a directional signal from liquid scintillator detectors.Broader impacts: Undergraduate research is critical for recruiting and retaining physics students. This award will be used to improve opportunities for transfer students. A seminar series on succeeding as a physics major will be developed and presented at UCLA. A modified version of the series will also be presented at Santa Monica College. Furthermore, this grant will sponsor an additional slot in UCLA's Research Experiences for Undergraduates (REU) program.