Rare Event Searches at MIT

暗物质的本质是物理学最大的谜团之一。仅次于此的是宇宙中观测到的物质-反物质不对称的奥秘。轴子和马约拉纳中微子分别是尚未被发现的粒子，它们可能参与提供答案。轴子是一个很好的暗物质候选者，而马约拉纳中微子可以通过一个被称为轻生的过程产生宇宙的物质反物质不对称。罕见事件搜索是探索这些模型的唯一可行技术。因此，粒子物理学和核物理学的实验类型分别是最优先考虑的。该奖项将支持两项工作：用ABRACADABRA和DMRadio寻找微型电子轴子，以及无中微子双β衰变（0νββ）搜索KamLAND-Zen。这些努力建立在麻省理工学院小组的专业知识基础上，两项实验都使用了从深度学习到量子传感的新型多学科技术。更广泛的影响是双重的：为低温实验开发强大的隔振装置和培养下一代科学家。这个奖项将把从引力波探测到0νββ的不同社区聚集在一起，参加一个关于隔振的研讨会。本科生研究是学院的优先事项，因为它对招收和留住物理系学生至关重要。该奖项将资助麻省理工学院的一项本科生研究，并开发最佳实践，以吸引不同群体的学生参与STEM领域。弦和QCD轴子模型激发了对质量低于10^−6 eV的轴子暗物质的搜索。ABRACADABRA和暗物质无线电实验联合起来，作为DMRadio实验来探测这个质量范围。这是一个建立在ABRA-10 cm成功基础上的分阶段程序，扩展到DMRadio-50L以测试谐振读数，然后移动到更高的m^3尺度频率以搜索到QCD轴子。在KamLAND-Zen实验中寻找中微子双β衰变。深度学习技术将用于训练和测试搜索算法。由于许多蒙特卡罗（MC）输入具有相同的总效应，并且实验是根据光曲线在不同维度上的微小偏差进行调整的，因此KLZ探测器的调谐是非平凡的。该小组正在探索生成对抗网络（GAN）作为解决这个问题的一种方法。gan的主要用途是生成人工图像。对抗网络擅长提取许多小特征，以提高分类器对候选罕见事件的准确性。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。

The nature of dark matter is one of the great mysteries of physics. Second only to this is the mystery of the universe’s observed matter-antimatter asymmetry. Axions and Majorana neutrinos, respectively, are as-yet undiscovered particles which may participate in providing the answers. Axions are a well-motivated dark matter candidate while Majorana neutrinos can produce the matter antimatter asymmetry of the universe through a process called leptogenesis. Rare-event searches are the only feasible techniques to explore these models. For this reason, the types of experiments are the highest priority for particle and nuclear physics, respectively. This award will support two efforts: the search for micro-eV axions with ABRACADABRA and DMRadio, and the neutrinoless double-beta decay (0νββ) search KamLAND-Zen. These efforts build on the expertise within the MIT group, and both experimental efforts use novel multidisciplinary techniques from deep learning to quantum sensing.The broader impacts are two-fold: the development of robust vibration isolation for cryogenic experiments and the training of the next generation of scientists. This award will bring together disparate communities from gravitational wave detection to 0νββ for a workshop on vibration isolation. Undergraduate research is a priority for the PI since it is critical for recruiting and retaining physics students. This award will sponsor a study of undergraduate research at MIT and the development of best practices to engage a diverse group of students in STEM fields.The string and QCD axion models motivate a search for Axion dark matter with masses below 10^−6 eV. The ABRACADABRA and Dark Matter Radio experiments have joined forces to probe this mass-range as the DMRadio experiment. This is a staged program that builds on the success of ABRA-10 cm, expands to DMRadio-50L to test the resonant readout, then moves to higher frequencies at the m^3-scale to search down to the QCD axion. Neutrinoless double beta decay is sought in the KamLAND-Zen experiment. Deep learning techniques will be used for training and benchmarking the search algorithm. The tuning of the KLZ detector is non-trivial because many of the Monte Carlo (MC) inputs have the same gross effect and the experiments are tuning on minor deviations of the light curves in various dimensions. The group is exploring generative adversarial networks (GAN) as a way to tackle this problem. The main use of GANs is the generation of artificial images. The adversarial network is good at picking up many small features to increase the accuracy of the classifier for candidate rare events.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.