Beyond the Standard Model Physics

该奖项将为在欧洲核子研究中心（位于瑞士日内瓦的粒子物理实验室）的大型强子对撞机（LHC）进行ATLAS实验的一个小组提供支持。大型强子对撞机和大型粒子探测器阿特拉斯（ATLAS）是利用美国国家科学基金会（NSF）和世界各地其他机构的资金建造的基础科学工具。他们的主要目标之一是找到希格斯玻色子，这是历史上成功的“标准模型”（SM）中的最后一个粒子，该模型在很大程度上解释了宇宙中形成物质的已知粒子的存在以及它们之间的作用力。这一努力取得了成功。实验的下一步是寻找超越标准模型（BSM）的物理证据，例如，这些证据可能解释构成宇宙大部分质量的神秘“暗物质”的存在。大型强子对撞机目前正处于第二阶段，能量几乎是之前探测的两倍，事件样本也显著增加。有可能在更高的能量和更高的事件统计中出现BSM物理的证据。华盛顿大学的研究人员正在通过两种方法寻找新的BSM物理。第一种是通过研究希格斯玻色子的成对产生，每个玻色子衰变成b-夸克。这项工作强调了识别b-夸克衰变和背景估计的专门分析技术。第二种方法是寻找中性的长寿命粒子，这些粒子在远离大型强子对撞机相互作用点（高能束流碰撞的地方）的ATLAS探测器体积中衰变。这项研究使用由该小组开发的定制触发器来选择从碰撞点偏移的衰变，并将寻找长寿命的中性希格斯玻色子以及广泛的其他BSM现象。该小组通过公开传播ATLAS的结果，支持更广泛的影响方案，重点是培训来自代表性不足群体的学生。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。

This award will provide support to a group working on the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, a particle physics laboratory in Geneva, Switzerland. The LHC machine and ATLAS, a large particle detector facility, were built as basic science tools using funds from NSF and other agencies around the world. One of their primary objectives was to find the Higgs Boson, the last particle in the historically successful "Standard Model" (SM) that accounts for so much of the existence of, and forces between, known particles forming the matter in the universe. This effort has been successful. The next step in the experiments is to look for evidence for physics Beyond the Standard Model (BSM) that might, for instance, account for the presence of the mysterious "Dark Matter" that makes up so much of the mass of the universe. The LHC is currently in the midst of Run 2, at almost twice the energy explored earlier and with significantly increased event samples. It is possible that evidence for BSM physics could emerge at this higher energy and with the higher event statistics. The investigators from the University of Washington are searching for the new BSM physics through two approaches. The first is through the study of pair production of Higgs Bosons, with each Boson decaying into b-quarks. This work emphasizes specialized analytical techniques for identifying b-quark decays and for background estimation. The second approach is a search for neutral long-lived particles that decay in the ATLAS detector volume far from the LHC interaction point, where the high-energy beams collide. This search uses custom triggers developed by the group to select decays displaced from the collision point and will search for long-lived neutral Higgs bosons as well as a broad range of other BSM phenomena.The group supports a broader impact program through public dissemination of the results from ATLAS, with emphasis on training students from underrepresented groups.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.