WOU-MMA: cosmic-RAY physics with icecube 2026 - 2029

The National Science Foundation Division of Physics awarded the University of Delaware $800,000 on August 1, 2026, under the Mathematical and Physical Sciences program (CFDA 47.049) to support cosmic-ray physics analysis using data collected by the IceCube Neutrino Observatory at the South Pole Station.

The award funds scientists at multiple U.S. institutions to continue analyzing cosmic-ray data from IceCube, which uses one cubic kilometer of Antarctic ice as a particle detector paired with IceTop, a surface array of 162 particle detectors. These instruments detect high-energy cosmic rays that strike Earth's atmosphere and produce cascades of secondary particles. The research investigates the origins of the highest-energy galactic cosmic rays and their interactions in Earth's atmosphere, while also examining related phenomena in the heliosphere, the Sun, and Earth's atmosphere. The project advances machine-learning techniques for cosmic-ray analysis and supports education and workforce development through IceCube masterclasses for high school students, research opportunities for university students, and STEM engagement programs.

Performance of work occurs in Newark, Delaware. The period of performance runs from August 1, 2026, through July 31, 2027. The assistance type is a Project Grant.

Abstract

This award supports scientists at several U.S. Institutions as they continue analyzing cosmic-RAY data collected by the icecube neutrino observatory (ICNO) at the south pole station. Icecube uses one cubic kilometer of clear antarctic ICE as a giant particle detector. The detector is paired with icetop, a surface array of 162 particle detectors. Together, these instruments detect brief flashes of light produced when high-energy cosmic rays strike earth's atmosphere and create cascades of secondary particles. Although ICNO was originally designed to detect neutrinos, IT has also become one of the world's leading observatories for studying high-energy cosmic rays. Its measurements help scientists investigate where the highest-energy galactic cosmic rays come from and how they interact in earth's atmosphere. In addition to advancing fundamental research in astrophysics and particle physics, this project supports related studies of the heliosphere, the sun, and earth's atmosphere because solar activity and atmospheric conditions can affect the cosmic-RAY signals measured by icecube. The project advances the national science foundation's goals for multi-messenger astrophysics and polar science while contributing to the development of artificial intelligence through the use of machine-learning techniques that are central to many cosmic-RAY analyses. The award also supports education, workforce development, and public outreach through activities such as ICNO masterclasses for high school students, research opportunities for university students, and other stem engagement programs. ICNO's unique location at the south pole, combined with its groundbreaking science, has generated broad public interest through news coverage, educational materials, websites, and social media. ICNO's three-dimensional design, which combines the icetop surface array with the deep in-ICE detector, also makes IT one of the world's most capable instruments for studying cosmic-RAY air showers. These air showers are cascades of particles produced when high-energy cosmic rays enter earth's atmosphere. Icetop measures the electromagnetic particles and low-energy muons that reach the surface, while the in-ICE detector records higher-energy muons that penetrate deep into the antarctic ICE. This unique combination provides information that cannot be obtained by any other observatory. In addition to its role in neutrino astronomy, ICNO measures important properties of galactic cosmic rays, including their energy spectrum, mass composition, and arrival directions. During this two-year award, the research team will continue these studies while focusing on projects that can produce significant scientific results within the available time and resources. ICNO has already produced the world's most sensitive measurements of large-scale cosmic-RAY anisotropy in the southern hemisphere at teraelectronvolt (TEV) to petaelectronvolt (PEV) energies. By combining ICNO observations with data from other observatories, researchers will improve their understanding of the structure, energy dependence, and origin of these directional patterns. The project will also improve measurements of the cosmic-RAY energy spectrum by reducing systematic uncertainties through new analysis methods and by incorporating data from recently deployed surface detectors. Finally, the project will continue using ICNO's combined surface and deep measurements to test models of high-energy particle interactions in the atmosphere. These studies include evaluating the latest hadronic interaction models used to simulate cosmic-RAY air showers and making unique measurements of high-energy atmospheric leptons. Together, these efforts will improve our understanding of both the astrophysical sources of cosmic rays and the particle physics that governs their interactions in earth's atmosphere. 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.- subawards are planned for this award.