Study of the Highest Energy Cosmic Rays with the Pierre Auger Observatory

皮埃尔·奥格尔天文台(Auger)的发现改变了我们对超高能宇宙射线(UHECR)及其来源的理解。该奖项支持科罗拉多矿业学院和凯斯西储大学的天体粒子小组，他们是Auger的主要贡献者，具有重要的领导作用。他们将对探测器和能量系统学、大气层和天体物理学进行创新研究。长期以来，解开UHECR是如何加速的一直是多信使天体物理学的圣杯，需要俄歇的统计能力，加上改进的探测器和先进的数据分析方法。继续了解俄歇相对和绝对能量尺度的工作将解决现有的内部和与其他实验的差异。这项研究产生了与气候变化和对流风暴有关的数据：包括分析这些数据的工作，以及气溶胶数据，这些数据在气候变化中的作用尚未得到很好的了解。这些研究小组还将继续参与基于这项研究的本科生设计项目。虽然能谱测量已经确凿地证实了通量抑制的存在，但成分研究表明，从轻到重的基色在脚踝上方的演化似乎与已知的效应不相容。目前对能谱、各向异性、粒子组成、中微子极限、光子极限和p-空气截面的测量表明，俄歇对高能宇宙有着前所未有的看法，并在大型强子对撞机之外的能量范围内接触到粒子物理。俄歇结果将使研究小组能够利用和理解天空中UHECR源的更微妙的表现。此外，这项研究调查了电离层中来自加热电子的鲜为人知的启动过程，使用俄歇荧光探测器站的独特能力来研究称为ELES的瞬时发光事件。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The discoveries made by the Pierre Auger Observatory (Auger) have transformed our understanding of ultra-high energy cosmic rays (UHECRs) and their sources. This award supports the astro-particle groups at the Colorado School of Mines and Case Western Reserve University, who are major contributors in Auger with significant leadership roles. They will carry out innovative studies of detector and energy systematics, atmospherics, and astrophysics. Unraveling how UHECRs are accelerated has been the holy grail of multi-messenger astrophysics for a long time and requires the statistical power of Auger, augmented by an improved detector and by advanced data analysis methods. Continued work to understand the relative and absolute energy scales of Auger will resolve existing discrepancies, both internal and with other experiments. The research produces data that relate to climate change and convective storms: work is included to analyze those data, as well as data on aerosols, whose role in climate change is not well understood. The groups will also continue their involvement with undergraduate design projects based around the research.While energy spectrum measurements have firmly established the existence of flux suppression, composition studies suggest an evolution from light to heavier primaries above the ‘ankle’ that is seemingly incompatible with known effects. The current measurements of energy spectra, anisotropy, particle composition, neutrino limits, photon limits, and p-air cross section demonstrate that Auger has an unprecedented view of the high-energy universe and access to particle physics at energies beyond the Large Hadron Collider. Auger results will enable the groups to both use and understand the more subtle manifestations of UHECR sources in the sky. In addition, this research investigates poorly understood initiation processes coming from heated electrons in the ionosphere, using the unique capabilities of the Auger Fluorescence Detector stations to study the Transient Luminescence Events known as elves.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.