Advanced Event Reconstruction and the Study of Prompt Muons in Ultrahigh Energy Extensive Air Showers in IceCube

冰立方中微子天文台发现了能量范围在20 TeV和10 PeV之间的高能中微子的外星成分，但它们的具体来源仍然不明。为了更好地理解这些中微子的大气和天体物理性质，在相应的能量区域中精确建模大气μ子和中微子是重中之重。在一个相关的领域，在过去的几十年里，已经发现了银河宇宙射线的起源和传播。一个关键的问题是如何过渡到起源于银河系外的高能宇宙射线。要解决这个问题，需要对10^15 eV（PeV）到10^18 eV（EeV）之间的宇宙射线初级粒子的能量和质量组成进行可靠的测量。该小组将开发新的分析方法，以便根据冰立方天文台获得的数据更好地确定这些极高能量粒子的能量和方向。该项目的更广泛影响将是教育和协同作用。该奖项将为一名研究生的支持和一些旅行提供资金。凭借其表面阵列IceTop，IceCube为研究整个银河系到河外过渡区的宇宙射线及其诱导的大气μ子和中微子提供了独特的数据。该奖项的目标是：--用新的分析技术研究高能扩展空气簇射（EAS）中的瞬发μ子。与其他方法相比，该技术具有独特的优势，即瞬发μ子签名对宇宙线初级粒子质量组成不敏感;--表征在新改进的重建算法中的高能EAS前沿中的粒子的时间剩余涨落及其与角分辨率的关系，该算法解决了IceTop中高能EAS方向重建中的一个长期存在的问题;--R& D朝向一个统一的三维重建，直接从IceTop和InIce重合数据导出宇宙射线初级质量和能量。该奖项反映了NSF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 IceCube Neutrino Observatory has discovered an extraterrestrial component of high-energy neutrinos in the energy range between 20 TeV and 10 PeV, yet their specific sources remain unidentified. To better understand the atmospheric and astrophysical nature of these neutrinos, precise modeling of atmospheric muons and neutrinos in the corresponding energy region is among the top priorities. In a related field, there have been discoveries regarding the origin and propagation of Galactic cosmic rays in past decades. One key question concerns the transition to cosmic rays of extragalactic origin at ultrahigh energies. Answering this question requires reliable measurements of both the energy and mass composition of cosmic ray primary particles between 10^15 eV (PeV) and 10^18 eV (EeV). This group will develop new analysis methods for better determining the energies and directions of these very high energy particles based on the data obtained from the IceCube Observatory. The broader impacts of this project will be both educational and synergistic. This award will provide funds for the support of a graduate student and some travel.With its surface array IceTop, IceCube provides unique data for the study of cosmic rays in the entire Galactic to extragalactic transition region and the atmospheric muons and neutrinos induced by them. The goals of this award are:--The study of prompt muons in ultrahigh energy extensive air showers (EASs) with a new analysis technique. Comparing to other approaches, this technique has the unique advantage that the prompt muon signature is insensitive to the cosmic ray primary particle mass composition;--Characterization of the time residual fluctuation of particles in the ultrahigh energy EAS front and its relation to the angular resolution in a newly improved reconstruction algorithm that solved a long-standing problem in high energy EAS direction reconstruction in IceTop;--R&D toward a unified 3-dimensional reconstruction that derives cosmic ray primary mass and energy directly from IceTop and InIce coincident data.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.