The PA-Supported Neutrino Program at MIT

粒子物理学中只有一个领域积累了潜在的相关异常：中微子振荡，中微子在空间中传播时会改变其特征。二十多年来，在短基线中微子振荡实验中观察到与标准模型三个中微子期望的偏差。最常见的是，新物理学的解释除了三种活跃的中微子——电子、μ子和tau之外，还引入了一个单一的惰性中微子，称为3+1模型。然而，在该模型中，异常和相关的零结果并不自洽。考虑到这些差异，如果所有或甚至部分信号都是由于新的物理现象，那么潜在的物理现象一定比3+1模型更复杂。解决这一局势已成为该领域的高度优先事项。与许多超越标准模型的搜索不同，在这种情况下，我们必须探测的参数空间相对来说是很容易理解的。这个协调的冰立方和IsoDAR项目，作为这个项目的一部分，将深入探索这个空间，并提供涉及所有三种味道特征的新方法——甚至包括τ中微子。该PI已经开发了两个正在进行的，影响非常大的项目。第一个是100美元的台式介子计数器，这款产品已经在媒体上做过介绍。她将继续改进设计和说明，并在会议、学校和科学节上展示该设备。第二个是开发一种经过适度改进的IsoDAR回旋加速器，以生产稀有的医用同位素，包括Ac-225。冰立方可以独特地搜索无菌诱导的物质效应共振。作为唯一一个正在进行的tau-中微子识别能力的实验，最近在一次成功的天体物理学tau-中微子候选搜索中得到了证明，该小组将使用冰立方的数据首次搜索与异常相关的μ -中微子- tau-中微子共振。他们将把搜索结果整合到该集团十多年来一直在进行的全球匹配中。IsoDAR正在从研发向设备建造过渡。该小组计划对他们开发的变革性射频四极杆技术进行校准和调试，以确定IsoDAR能够实现其通量目标。因此，IceCube+IsoDAR结合了一个协调的物理项目，为初级科学家提供了粒子物理学各个阶段的经验：现象学、硬件、软件和分析。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

There is only one area of particle physics with an accumulation of potentially-related anomalies: neutrino oscillations, where neutrinos change their character as they propagate through space. For more than two decades, deviations from the Standard Model three-neutrino expectation have been observed in short baseline neutrino oscillation experiments. Most commonly, new-physics explanations introduce a single sterile neutrino in addition to the three active flavors, electron, muon, and tau, called a 3+1 model. However, within this model, the anomalies and relevant null results are not self-consistent. Given these discrepancies, if all, or even some, of the signals are due to new physics, then the underlying physics must be more complicated than a 3+1 model. Resolving the situation has become a high priority for the field. Unlike many beyond-Standard-Model searches, this is a case where the parameter space we must probe is relatively well-understood. This coordinated IceCube and IsoDAR program, which is developed as part of this project, will explore this space in depth, and offer new approaches involving all three flavor signatures -- even tau-neutrinos.This PI has developed two ongoing, unusually-impactful programs. The first is the $100 desktop muon counter, which has been featured in the press. She will continue to improve the design and instructions, and to present the device at conferences, schools, and science festivals. The second is development of a modestly modified IsoDAR cyclotron to produce rare medical isotopes, including Ac-225. IceCube can uniquely search for sterile-induced matter-effect resonances. As the only on-going experiment with tau-neutrino identification capability, recently demonstrated in a successful astrophysical tau-neutrino candidate search, the group will use IceCube data for the first search for anomaly-related muon-neutrino - tau-neutrino resonances. They will integrate the results of their searches into global fits that the group has performed for more than a decade. IsoDAR is transitioning from R&D to construction of equipment. The group plans to calibrate and commission the transformative radio-frequency quadrupole technology that they have developed, establishing that IsoDAR can meet its flux goals. Thus, along with a coordinated physics program, the IceCube+IsoDAR combination offers the junior scientists experience at every stage of particle physics: phenomenology, hardware, software, and analysis.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.